Welcome to our frequently asked questions. Browse them all or toggle by product or topic.

Where is your California Proposition 65 Warning?

You can download the document here 

This applies to all Cambrionix system products and OEM modules.

Please read and understand this document prior to installation or use.

Where can I see your safety guidelines?

You can download the document here 

This applies to all Cambrionix system products and OEM modules.

Please read and understand this document prior to installation or use.

Using Apple Thunderbolt 3 to Thunderbolt 2 with Cambrionix products?

Can I use an Apple Thunderbolt 3 to Thunderbolt 2 adaptor with Cambrionix products?

Yes, you can.

If you have a Thunderbolt 2 host computer and a Thunderbolt 3 product from Cambrionix, you can use the adaptor to connect the two devices together – but since a Thunderbolt 2 host computer is only able to offer 20Gbps data speed, the Cambrionix Thunderbolt 3 product will naturally operate slower.

Connecting a Thunderbolt 3 product to a Thunderbolt 2 host computer will make the Thunderbolt 3 product work at half the speed (20Gbps vs 40Gbps).

If you have a Thunderbolt 3 host computer and a Thunderbolt 2 product from Cambrionix, you can use the adaptor to connect the two devices together – but since a Thunderbolt 3 host computer is able to offer 40Gbps data speed, the Cambrionix Thunderbolt 2 product will operate at its standard 20Gbps data speed (Thunderbolt 2 only supports 20Gbps, whereas Thunderbolt 3 can support 20Gbps or 40Gbps depending on the host/cable type).

Connecting a Thunderbolt 2 product to a Thunderbolt 3 host computer does not make the Thunderbolt 2 product work faster. The Thunderbolt 2 product will simply work as expected.

So, yes, you can use the Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter with Cambrionix products and Thunderbolt 2 or Thunderbolt 3 host computers.

The adaptor can be purchased via the Apple website and the price is around £50.

EtherSync – How do I download a log or journal file using Webmin?

How do I download a log or journal file from the EtherSync USB over IP product?

It is often helpful to provide Cambrionix with the journal or log file from an EtherSync unit that is not behaving as expected. This can help Cambrionix engineers diagnose a problem with your EtherSync product.

This is done by connecting to the EtherSync unit’s Webmin interface, replace the xxyyzz in the below link with the value for your unit, by default this is the last six digits from the MAC address. If you have changed the host name of your EtherSync unit, then you will need to use the name that you assigned to it instead.


The username is ‘admin’ and the password is recorded on the sticker on the bottom of the EtherSync unit. Unfortunately the font of the label printer is not the best and so you will need to take care about the differences between ‘O’ and ‘0’ and uppercase ‘i’ with lowercase ‘L’ etc., it is all case sensitive.

To download the journal, open the ‘System’ group from the left hand navigation panel and click on ‘Cambrionix Linux options’. The journal file can be downloaded by clicking the ‘Download’ button immediately below the heading ‘Journal file download’.

EtherSync – How to perform a factory reset?

How do I perform a factory reset on an EtherSync USB over IP product?

Thankfully there are two ways to perform a factory reset, one remotely via software (Webmin) and one using the traditional ‘paperclip in a hole’ method.

Performing a factory reset remotely using Webmin:

Sometimes a factory reset may need to be performed. This may be because the unit is being re-purposed or else under the direction of Cambrionix Technical Support.

This is done by connecting to the EtherSync unit’s Webmin interface, replace the xxyyzz in the below link with the value for your unit, by default this is the last six digits from the MAC address. If you have changed the host name of your EtherSync unit, then you will need to use the name that you assigned to it instead.


The username is ‘admin’ and the password is recorded on the sticker on the bottom of the EtherSync unit. Unfortunately the font of the label printer is not the best and so you will need to take care about the differences between ‘O’ and ‘0’ and uppercase ‘i’ with lowercase ‘L’ etc., it is all case sensitive.

To perform the factory reset, open the ‘System’ group from the left hand navigation panel and click on ‘Cambrionix Linux options’. The factory reset can be performed by clicking the ‘Factory Reset’ button immediately below the heading ‘Factory Reset’. If you wish to retain any customised network settings then you can use the button ‘Factory Reset, but keep network settings’ instead. You will then need to confirm the action.

After confirming the factory reset, you may get an error message about failing to find File/Basename.pm. This message is benign and can be ignored, the factory reset is not affected by this error.

Performing a factory reset locally:

If you need to restore an EtherSync unit to factory settings and cannot connect to it via the network, you can force a factory reset with this procedure.

You will need a tool to press the switch behind the hole below USB port 2. A paper clip straightened out should work.
Power the EtherSync ‘on’ and then press the switch within a couple of seconds. Continue to hold the switch pressed until the two red LEDs start to flash. This should take up to about 40 seconds from power on. Once you release the switch the unit will reboot after clearing all settings. It is now reset to factory defaults.

The PDF below shows how to perform the factory reset locally using the hidden front-panel switch.

What is biassed-mode?

Biassed-mode is a mode which you can use via our API (or terminal interface) which places a downstream USB port into a state whereby it only senses a device attach or detach event, it does not allow charging.

Because an attached device may only draw a small amount of current (less than 1mA), the VBUS current sensing electronics requires a large-value sense (or ‘shunt’) resistor in series with the VBUS connection in order to generate a measurable voltage across it.

Voltage = Current x Resistance (Ohms Law).

The upside to using a large-value sense-resistor is that we can measure low currents (such as those associated with a device being attached to a port), the downside is that if the attached device attempts to draw more than 1mA or so, the VBUS voltage will drop below the USB specified lower limit.

In summary, biassed-mode is a mode which is used purely for determining whether a device is attached to a downstream port. It should not be used as a means to charge a device.

For details about how to switch into and out of biassed-mode, please take a look at our API Reference document by clicking here.

Current measurement

Current measurement

How does the PowerPad15S (PP15S) compare to the Bretford PowerSync D20?

The Bretford PowerSync D20 is a product which offers a basic sub-set of the features from a PowerPad15S so the two products are in some way comparable.

The major differences and things for/against each product are outlined below.

Download our PDF comparison which gives more detail along with a simple side by side feature comparison.


The Bretford D20 offers basic features at a premium price whereas the Cambrionix PowerPad15S does everything that the Bretford D20 does but in a more compact package, with less cost per port, with more safety certification plus the addition of port monitoring and control via either an application programming interface or GUI app.


The Bretford D20 is aimed squarely at use within the classroom where having the power supply inside the box could mean one less thing to lose. The PowerPad15S is a more professional device offering features far in excess of the D20 for professional use.


The Bretford D20 is certified for use in the USA (with its UL Listing and FCC Part 15 Certification) whereas the Cambrionix PowerPad15S is certified for use in many more countries across the globe including Europe.


The D20 includes a set of cables for connection to iOS devices (you can choose either Lightning or the older 30way connector) whereas the PowerPad15S works will ALL USB chargeable devices, not just iOS devices. Cambrionix also believes that an extra set of cables is unnecessary cost which is included in the D20 price. We estimate the additional cost for the extra cables should be in the region of around £10 (~$13) per cable for a decent MFi Certified example.


The ‘per-port’ cost of the Cambrionix PowerPad15S is less than half of the Bretford D20 even taking into account the D20 being shipped with cables. The per-port cost is an important cost comparison between products as many of them have different port numbers. To put this into perspective, if you were to invest the same amount of money as the D20 costs into PowerPad15S units, you would have over twice the amount of charge and sync ports. If you connect the PowerPad15S units to separate USB host controller ports on your host computer you will provision/update/restore more mobile devices in less time than the D20.


Both products work seamlessly with Apple Configurator.


The Bretford D20 will not charge iOS devices during a sync (data transfer) process as there is no hardware support for CDP (Charging Downstream Port). This will mean than during an iOS update/restore/provisioning your iOS battery level will deplete. This is not ideal because sync tasks using a product such as Apple Configurator can take a long time to complete when so many iOS devices are connected. The Cambrionix PowerPad15S fully supports CDP as part of its firmware controlled suite of charging profiles. This means that whenever an iOS device (or any other device which supports CDP etc) is connected to the PowerPad15S it will be charging at the maximum rate that the manufacturer allows.


This brief review has been written by Cambrionix after our internal lab testing of the Bretford D20. We have tried to be as unbiassed as possible.

If you would like to verify any of the details within this review yourself you can find details of the Bretford D20 and Cambrionix PowerPad15S at the following links:




If sync speed is a priority to you, and you would like to perform iOS provisioning/updates/restores 10x faster than both the Bretford D20 or the PowerPad15S, the Cambrionix ThunderSync16 is a better choice. The link below takes you to the ThunderSync16 product page. Again, the ThunderSync16 offers all of the PowerPad15S features and adds an increased iOS charging level (2.4Amp/12W) and dual LEDs per port. ThunderSync16 is 10x faster than the D20 and also smaller and lower cost. ThunderSync16 uses Thunderbolt Technology to achieve incredibly fast sync speeds.


If you would like a demonstration or an evaluation unit for any Cambrionix product please get in touch at enquiries@cambrionix.com and we can discuss your requirements and eligibility.


How can I get notified of software updates for the API, LiveViewer etc?
Do Cambrionix offer an intelligent USB Power Distribution Unit or PDU?


A number of Cambrionix products can be called an intelligent USB PDU since they:

  • Provide power to multiple USB ports.
  • Allow the user to choose, programmatically (or via a GUI), which ports are powered or off.
  • Measure the current and power consumption from a particular port.
  • Provide many safety features to ensure that PDU faults to do not damage connected devices and that connected devices cannot damage the PDU.
  • Offer a high level of safety certification to ensure that whatever system they are designed-into is safe.

Switching individual downstream port power (VBUS) on or off can be achieved programmatically using our API, via a terminal interface, or by using our LiveViewer App which has a GUI.

This allows you to have complete control over your USB devices – essential when designing mobile device or cellphone testing rigs/racks such as this example from Facebook which was featured on The Verge in 2016:


U8S: Where can I connect a fan onto a U8S-EXT to prevent over-temperature shutdown.

The U8S-EXT (the 12V input version of the U8S) has an on-board 100W DC-DC converter to convert the 12V input to the 5.2V which the U8S requires for the downstream USB ports.

No DC-DC converter is 100% efficient therefore, as a result of the conversion, it generates some amount of heat.

The U8S-EXT may, in some instances, require forced cooling across its DC-DC converter in order to keep it within acceptable temperature limits. Without this forced cooling, the U8S-EXT firmware may sense a temperature level which is deemed too high. In this instance, the U8S-EXT would power-down the USB ports to reduce the load on the DC-DC converter and bring the temperature down to a safe level.

The temperature can be monitored via our API, LiveViewer App and also the command line interface. We have a shut off temperature of 65deg C.

We recommend a 40mm fan with a 10mm depth, these are readily available, low cost (around $2) and provide enough cooling when placed above or beside the DC-DC converter. Very little airflow is required to keep the DC-DC converter within limits, but fan position should be evaluated under your maximum operating ambient temperature to ensure that the U8S-EXT temperature (as read within LiveViewer) is maintained below 60deg C.

Please contact Cambrionix for advice about thermal considerations within your design and we will be happy to help.


Where to connect a fan to a U8S-EXT

Where to measure temperature on a U8S-EXT

USB Endpoint Limitation – what is it, and which Cambrionix products can fix it?

The ‘USB Endpoint Limitation’ is something which can cause issues with users who connect many USB devices to a host computer. Typically you will see an error relating to running out of USB resources, or similar, on the the host computer. Worst-case you will not see any warning or error message, your USB devices (or some of them) may simply fail to operate correctly or become intermittent.

The USB Endpoint Limitation only applies to xHCI host controllers (USB3.0 Host Controllers) on the computer motherboard. These host controllers typically offer between 64 and 128 USB endpoints (not to be confused with the amount of USB devices which can be connected onto a single USB port which is 127).

The problem with the limited number of endpoints provided by the host controller is that many USB devices enumerate as more than one endpoint. A device could enumerate and request, for instance, 5 endpoints. At this point, if your host controller only has 64 available endpoints you would only be able to connect 64/5 devices to that host controller, or 12 devices. Do note that all USB devices, including USB hubs, require endpoints.

Because the limitation applies to the host controller on the computer motherboard, it is possible to avoid the limitation by using a different host interface such as Thunderbolt.

Our Thunderbolt products (both Thunderbolt 2 and 3) do not use the motherboard USB host controller since the connection is Thunderbolt rather than USB. We then use multiple PCIe USB host controllers within our Thunderbolt products to provide the downstream USB ports.

The hardware architecture within our Thunderbolt products is such that each downstream USB port has at least 16 USB endpoints. This effectively removes the USB Endpoint Limitation.

To find out how our Thunderbolt products can help you, please contact us 



What do the certification marks such as UL, FCC and CE mean on Cambrionix products?

Cambrionix products have a number of certification marks on them, these certification marks are required to be able to legally ship to various countries such as the USA.

Some of the marks relate to safety certification, some are there to show that the products comply with EMC (Electro-Magnetic Compliance) requirements.

EMC compliance, in essence, means that our products or modules will not interfere with other, nearby devices such as radios, cellphones, medical implants, computers etc. It also means that other, nearby devices cannot interfere with the operation of our products/modules and cause them to malfunction.

Safety certification ensures that our products are designed to be safe to use in their intended manner.

Cambrionix, as a company, has made the decision to use external companies for all safety and EMC certification such that the results are traceable, valid and compliant. We only use accredited NRTL (Nationally Recognised Testing Laboratories) such as the Underwriters Laboratory (UL). Our UL Listed and Recognised products/modules are traceable via UL themselves.

This helpful PDF summarises the most common certification marks you will find on Cambrionix products along with what they mean and which countries they apply to. 

Apple Watch: How can I charge and monitor multiple Apple Watches with Cambrionix products?

The Apple Watch uses wireless charging via a small pad which is magnetically located onto the rear of the watch. This pad is on the end of a USB cable with a USB-A connector on the other end.

Charging, and monitoring the charging process of the Apple Watch, is easy with most Cambrionix products.

Use a PowerPad15C to charge and monitor 15 Apple Watches simultaneously – download the PDF now

U8/U16 LED/LCD Front panel: What are the electrical connections and where are the reference designs?

The U8 and the U16 can both accept a front panel – either an LCD or LED type.

The front panel can convey information such as charging status, whether a device is charged, whether its in data/sync mode, if the port is ‘off’ etc.

Both the LED and LCD front panels operate automatically but can also be controlled via our API if you wish. By using our API you are able to switch LEDs on/off and, if you are using an LCD display, send arbitrary text to the LCD for user feedback, help or error messages. You can even read front panel switches (or door switches) and inputs from other parts of your system.

Cambrionix supply reference designs for LED and LCD displays and they can be found below. We also have limited numbers of LED/LCD front panels available to purchase.

The files below show the PDF schematic designs for LCD and LED panels for both the U8 and U16 as well as CAD files in Altium Designer format plus some information about how to connect the panels.

Cambrionix can offer design support for your own front panel design should this be required.

U8 LED Schematic PDF – CBRX1088V1_SCH


U8 LCD Schematic PDF – CBRX1087V1_SCH


U16 LED Schematic PDF – CBRX1090V1_SCH


U16 LCD Schematic PDF – CBRX1089V2_SCH


U8 and U16 Front Panel Reference



SuperSync15: My Windows computer asks for CDC or USB drivers, where can I find these?

SuperSync15 should ‘just work’ with most recent operating systems from both Apple and Microsoft. In this instance you wouldn’t be required to install drivers for SuperSync to work.

If you are using an older version of Windows, for instance Windows 7, you may be prompted to install drivers when you first connect SuperSync.

To install the drivers, open ‘device manager’, double click on the item with the warning symbol next to it, choose ‘update driver’ and navigate to the directory where the correct driver is located.

The ZIP file here contains 2 drivers, one for CDC and one for USB. These are the correct drivers for SuperSync15.

ThunderSync: Can I use the 2 Thunderbolt ports to connect 2 different host computers?


ThunderSync has 2 seperate host ports (the 2 Thunderbolt ports next to the power input connector) for a different reason:

In order for our ThunderSync product to become Thunderbolt Certified by Intel, we were required to offer two Thunderbolt ports. These ports can be used to connect additional Thunderbolt devices (such as monitors, storage etc) in the Thunderbolt chain. You can also use the 2nd Thunderbolt port to add additional ThunderSync products to increase the number of downstream USB ports. Here’s a link showing how to daisy-chain ThunderSync products.

You can think of the 2 Thunderbolt ports as being connected to a Thunderbolt ‘hub’ internally.

So, in summary, the 2 Thunderbolt ports cannot be used to connect 2 different host computers.

Shipping: Can I use my own courier / carrier such as FedEx, UPS, DHL?

Arranging your own shipping.

If you would prefer to arrange for your own collection we can have the warehouse pack up the order and send us the weights and dimensions. We will then send this on to you along with the collection address.

If you would like to arrange your own shipping you must:

  • Prepare all labels and documentation for the shipping. For international shipments this includes a commercial invoice which has to be attached for customs clearance. The commercial invoice needs to include a product description and item value.
  • Book a collection with your chosen courier and schedule the collection. The warehouse is open for collection until 5pm GMT
  • Email the labels and any other paperwork to your sales manager who will forward it on to the warehouse to be attached to your shipment.

Please note that if you arrange your own shipping, Cambrionix are not responsible for the loss, damage or delay of any deliveries once collected from our warehouse, and will not be able to liaise with the courier on your behalf.

Shipping: When can I expect to receive my order?

After receiving payment we will send a pick list of your order to our warehouse who will pack your units and arrange the shipping. It can take up to 24 hours to be processed in our warehouse. The warehouse ship with UPS and depending on your location delivery is usually from 2-5 working days.

Shipping: Why do I get charged on some orders and not others?

This depends on the value of the shipment. For example, the Formal Clearance Threshold for the United States is $2,500.00. If your shipment is worth more than this it will be subject to Formal Clearance.

Shipping: My shipment is being held by customs. What can I do?

The majority of the time the courier will contact you directly if there is an Exception on your shipment. If they haven’t, we can contact our logistics company to push them to contact you to resolve the issue.

Please ensure that your contact details are correct at the time of order in case we need to get in touch.

Shipping: Can you let me know how much the import fee will be?


The fee is calculated by each country and Cambrionix will not quote you for this. The amount differs from country to country, and is charged on all sales transactions as a percentage of the value of the goods.

Shipping: Can Cambrionix pay the import fees to avoid a delivery delay?


These fees are decided by the Customs agency in each country and the importer of the goods is responsible for paying these taxes. Cambrionix is not responsible for these payments. If the shipment is returned to sender due to non-payment, there will be an additional shipping fee for us to re-ship to you.

Shipping: Why is the courier requesting a payment before delivery?

Why is the courier requesting a payment before delivery even though I have paid for shipping?

The additional fees on deliveries are Customs Duties and Taxes and will need to be paid before your order will be delivered. Cambrionix will charge you for the shipping cost which does not include these fees. Most couriers will leave a card with instructions on how to pay this.

Can I use Cambrionix products for wireless charging?


Wireless charging is something which Cambrionix products can support by using wireless charging ‘pads’ connected to our products.

Many wireless charging pads require a 5V 2Amp (10W) input in order to operate, most of our products can supply more than that. As a result, we can power the wireless charging pads but also offer features which no other wireless charging system can. We can:

  • Monitor the current consumption of the wireless charger.
  • Enable and disable the wireless charger.
  • Detect when a device has been placed on the charging pad, or removed from it.
  • Determine how long a device has been attached and charging along with Watt-Hours.
  • Automate any of the above using our API, LiveViewer App or command line interface.

There are a number of Qi charging pads from the likes of Samsung and Belkin which can connect directly to our products. As a rule, if the pad has a USB port (typically a Micro-USB port) then we can power and control it.

Download our guide to how to connect wireless charging pads with our products.


Connecting a USB point of sale (PoS) terminal devices to Ethernet

Retailers are slowly moving away from legacy point of sale terminals in favour of lower cost card readers, tablet devices, printers and scanners. This gives them the flexibility to choose the devices which work best for them and create their own, bespoke point of sale terminal.

This can, however, create some problems.

Within a retail store, there may be a number of mobile terminals as well as a number of fixed terminals. If these terminals are created by using a number of USB devices (say and iPad, USB card reader, USB barcode scanner, USB printer, USB cash drawer etc) then they will all need to be charged/powered and will all require some form of data transfer from themselves to a computer.

The data transferred between the USB devices can either be to a local computer (under the desk which the terminal is placed onto, one per terminal) or can be to a computer/server in the back office. EtherSync addresses the latter ie. the terminals (comprised of USB devices) all connect to a back-office computer away from the front-of-store. EtherSync even has a built-in 2 port Gigabit Ethernet switch for connecting to both the in-store Ethernet network and also to legacy ‘Ethernet only’ devices.

Download our guide here

Find out more about EtherSync in a retail environment

What is the official specification for a USB Type-C cable or connector?

USB Type-C Cables and Connectors come in various types, lengths, current handling capability, etc etc.

Download the USB IF specification for USB Type-C here.

Note: Don’t forget that ‘Type-C’ is a connector, its not a new data transfer protocol!

Shipping: Can you ship worldwide?

Yes we can.

We sell the majority of our products to companies outside of the UK, so we are experienced in in all aspects of shipping.

Our warehouse can palletise and ship to anywhere on the globe by land, sea or air.

All of our products are shipped with DDU (Delivered, Duty-Unpaid) terms unless otherwise stated or agreed in advance.

We can also ship using your own courier should that be preferable.

If I use a USB3.0 hub, will I get faster data transfer?

If I use a USB3.0 USB Hub, will I automatically get faster data?

Possibly, not necessarily. It depends on a number of factors which aren’t immediately obvious!

To experience the full benefit of the USB3.0 increased data rate (5,000Mbps vs 480Mbps for USB2.0) both the device and the host computer must both support USB3.0. Also, any USB cables connected from the host to the Cambrionix product and from the Cambrionix products to the USB mobile device must be USB3.0.

In summary, all cables and hardware in the USB3.0 chain needs to support USB3.0 in order for there to be any speed benefit. The reason for this is that there USB2.0 and USB3.0 signals are treated separately i.e. they do not share the same pieces of copper wire for data. A USB3.0 connector and cable has the USB2.0 data signals as well as the USB3.0 data signals. This provides ‘backwards-compatibility’.

There are some useful infographics which you can download below.

Cambrionix - USB3 Infographic

Cambrionix – USB3 Infographic

Cambrionix – USB3 SuperSpeed Connector Pinout


How fast (bandwidth) can I transfer data with Cambrionix products?

Cambrionix offers a number of different products to cater for different USB data transfer speeds. There is a summary of the different data transfer speeds (also called bandwidth or data-rate) below:



Gigabit Ethernet






Thunderbolt 2


Thunderbolt 3


*Note: Mbps means Mega Bits Per Second


There are a number of factors which affect the real-world data transfer rate from the host computer to your USB devices including the USB device itself, the host computer specification and how many USB devices you connect to the Cambrionix product.

We can discuss your requirements to find the best Cambrionix solution for your needs.

Each of our product pages indicates the host interface and downstream speed.

Do Cambrionix products work with all mobile device manufacturers and operating systems?

All of our charge and sync (data) products work happily with all mobile device manufacturers and operating systems.

There are some Cambrionix ‘charge-only’ products, the MultiCharger Range, which are manufacturer specific.

The MC16-2.1 is designed to charge Apple iOS devices at 10W per port.

The MC14-2.4 is designed to charge Apple iOS devices at 12W per port.

The MC16-1.5 is designed to charge BC1.2 DCP supporting devices. This is compatible with the vast majority of modern Android devices.

Our API, command-line interface and EtherSync Connector software will work across all platforms and our LiveViewer App works with Mac and Windows OS’s.

What does BYOD (Bring Your Own Device) mean?

The content of this FAQ article is based upon Wikipedia entry:


The full Wikipedia article is available clicking here.

Bring your own device

Bring Your Own Device (BYOD)—also called bring your own technology(BYOT), bring your own phone (BYOP), and bring your own Personal Computer (BYOPC)—refers to the policy of permitting employees to bring personally owned devices (laptops, tablets, and smart phones) to their workplace, and to use those devices to access privileged company information and applications. The phenomenon is commonly referred to as IT consumerization.

BYOD is making significant inroads in the business world, with about 75% of employees in high growth markets such as Brazil and Russia and 44% in developed markets already using their own technology at work. Surveys have indicated that businesses are unable to stop employees from bringing personal devices into the workplace. Research is divided on benefits. One survey shows around 95% of employees stating they use at least one personal device for work.


The term BYOD first entered common use in 2009, courtesy of Intel when it recognized an increasing tendency among its employees to bring their own devices (i.e., smartphones, tablets and laptop computers) to work and connect them to the corporate network. However, it took until early 2011 before the term achieved any real prominence when IT services provider Unisys and software vendor Citrix Systems started to share their perceptions of this emergent trend. BYOD has been characterized as a feature of the “consumer enterprise” in which enterprises blend with consumers. This is a role reversal in that businesses used to be the driving force behind consumer technology innovations and trends.

In 2012, the U.S.A Equal Employment Opportunity Commission adopted a BYOD policy, but many employees continued to use their government-issued BlackBerrys because of concerns about billing, and the lack of alternative devices.

New trends

The proliferation of devices such as tablets and smartphones, which are now used by many people in their daily lives, has led to a number of companies, such as IBM, to allow employees to bring their own devices to work, due to perceived productivity gains and cost savings. The idea was initially rejected due to security concerns but more and more companies are now looking to incorporate BYOD policies, with 95% of respondents to a BYOD survey by Cisco saying they either already supported BYOD or were at least considering supporting it.

This new trend also prevents IT from having to continuously keep up with new technology available on the market, which in recent years has become a complex and constantly growing challenge.


The Middle East has one of the highest adoption rates (about 80%) of the practice worldwide in 2012.

According to research by Logicalis, high-growth markets (including Brazil, Russia, India, UAE, and Malaysia) demonstrate a much higher propensity to use their own device at work. Almost 75% of users in these countries did so, compared to 44% in the more mature developed markets.

In the UK, the CIPD Employee Outlook Survey 2013 revealed substantial variations by industry in the prevalence of BYOD.


Some reports have indicated productivity gains by employees. Companies like Workspot inc believe that BYOD may help employees be more productive. Others say it increases employee morale and convenience by using their own devices and makes the company look like a flexible and attractive employer. Many feel that BYOD can even be a means to attract new hires, pointing to a survey that indicates 44% of job seekers view an organization more positively if it supports their device.

Some industries are adopting BYOD quicker than others. A recent study by Cisco partners of BYOD practices stated that the education industry has the highest percentage of people using BYOD for work at 95.25.

A study by IBM says that 82% of employees think that smartphones play a critical role in business. The study also shows benefits of BYOD include increased productivity, employee satisfaction, and cost savings for the company. Increased productivity comes from a user being more comfortable with their personal device; being an expert user makes navigating the device easier, increasing productivity. Additionally, personal devices are often more cutting edge as company technology refreshes don’t happen as often. Employee satisfaction, or job satisfaction, occurs with BYOD by allowing the user to use the device they have selected as their own rather than one selected by the IT team. It also allows them to carry one device as opposed to one for work and one for personal use. Cost savings can occur on the company end because they now would not be responsible for furnishing the employee with a device, but is not a guarantee.


Although the ability to allow staff to work at any time from anywhere and on any device provides real business benefits; it also brings significant risks. To ensure information does not end up in the wrong hands, it’s imperative for companies to put security measures in place. According to an IDG survey, more than half of 1,600 senior IT security and technology purchase decision-makers reported serious violations of personal mobile device use.

Various risks arise from BYOD, and agencies such as the UK Fraud Advisory Panel encourage organisations to consider these and adopt a BYOD policy.

BYOD security relates strongly to the end node problem, wherein a device is used to access both sensitive and risky networks/service risk-averse organizations issue devices specifically for Internet use (this is termed Inverse-BYOD).

BYOD has resulted in data breaches. For example, if an employee uses a smartphone to access the company network and then loses that phone, untrusted parties could retrieve any unsecured data on the phone. Another type of security breach occurs when an employee leaves the company, they do not have to give back the device, so company applications and other data may still be present on their device.

Furthermore, people sometimes sell their devices and might forget to wipe sensitive information before selling the device or handing it down to a family member. Various members of the family often share certain devices such as tablets; a child may play games on his or her parent’s tablet and accidentally share sensitive content via email or through other means such as Dropbox.

IT security departments that wish to monitor usage of personal devices must ensure that they only monitor work related activities or activities that accesses company data or information.

Organizations who wish to adopt a BYOD policy must also consider how they will ensure that the devices which connect to the organisation’s network infrastructure to access sensitive information will be protected from malware. Traditionally if the device was owned by the organisation, the organisation would be able to dictate for what purposes the device may be used or what public sites may be accessed from the device. An organisation can typically expect users to use their own devices to connect to the Internet from private or public locations. The users could be susceptible from attacks originating from untethered browsing or could potentially access less secure or compromised sites that may contain harmful material and compromise the security of the device.

Software developers and device manufacturers constantly release security patches due to daily increase in the number of threats from malware. IT departments that support organisations with a BYOD policy must be prepared to have the necessary systems and processes in place that will apply the patches to protect systems against the known vulnerabilities to the various devices that users may choose to use. Ideally such departments should have agile systems that can quickly adopt the support necessary for new devices. Supporting a broad range of devices obviously carries a large administrative overhead. Organisations without a BYOD policy have the benefit of selecting a small number of devices to support, while organisations with a BYOD policy could also limit the number of supported devices, but this could defeat the objective of allowing users the freedom to completely choose their device of preference.

Several market and policies have emerged to address BYOD security concerns, including mobile device management (MDM), containerization and app virtualisation.

While MDM provides organizations with the ability to control applications and content on the device, research has revealed controversy related to employee privacy and usability issues that lead to resistance in some organisations. Corporate liability issues have also emerged when businesses wipe devices after employees leave the organisation.

A key issue of BYOD which is often overlooked is BYOD’s phone number problem, which raises the question of the ownership of the phone number. The issue becomes apparent when employees in sales or other customer-facing roles leave the company and take their phone number with them. Customers calling the number will then potentially be calling competitors which can lead to loss of business for BYOD enterprises.

International research reveals that only 20% of employees have signed a BYOD policy.

It is more difficult for the firm to manage and control the consumer technologies and make sure they serve the needs of the business. Firms need an efficient inventory management system that keeps track of which devices employees are using, where the device is located, whether it is being used, and what software it is equipped with.

If sensitive, classified, or criminal data lands on a U.S. government employee’s device, the device is subject to confiscation.

The USMC is seeking to outsource the security requirements of their BYOD policy to commercial carriers such as Sprint, Verizon, and AT&T.

Another important issue with BYOD is of scalability and capability. Many organisations today lack proper network infrastructure to handle the large traffic which will be generated when employees will start using different devices at the same time. Nowadays, employees use mobile devices as their primary devices and they demand performance which they are accustomed to. Earlier smartphones did not use a lot of data and it was easy for Wireless LAN to handle that amount of data, but today smartphones can access webpages as quickly as most PCs do and have applications that use radio and voice at high bandwidths, hence increasing demand from WLAN infrastructure.

Finally, there is confusion regarding the reimbursement for the use of a personal device. A recent court ruling in California indicates the need of reimbursement if an employee is required to use their personal device for work. In other cases, companies can have trouble navigating the tax implications of reimbursement and the best practices surrounding reimbursement for personal device use.

Personally owned, company enabled (POCE)

A personally owned device is any technology device that was purchased by an individual and was not issued by the agency. A personal device includes any portable technology like camera, USB flash drives, mobile wireless devices, tablets, laptops or any personal desktop computer.

The agency will maintain management control and authorize the use of personally owned devices and shall develop guidelines to define which employees can use their own devices, the types of devices they can use, and which applications and data they can access, process, or store.

Corporate owned, personally enabled (COPE)

As part of enterprise mobility, an alternative approach are corporate owned, personally enabled devices (COPE). With this policy the company purchases the devices to provide to their employees; the functionality of a private device is enabled to allow personal usage.

The company maintains all of these devices similarly to simplify its IT management; the organization will have permission to remotely delete all data on the device without incurring penalties and without violating the privacy of its employees.

Other policy considerations

BYOD policies can vary greatly from organization to organization depending on the concerns, risks, threats, and culture. As such, BYOD policies can differ in the level of flexibility given to employees to select device types. Some policies may dictate a narrow range of devices; others may allow a broader range of devices. Related to this, policies can be structured to prevent IT from having an unmanageable number of different device types to support. It’s also important to clearly state what areas of service and support are the employees’ responsibilities versus the company’s responsibility.

BYOD users often get help paying for their data plans with a stipend from their company. Also, there may be a policy aspect as to whether an employee should be paid overtime for answering phone calls or checking email after hours or on weekends. Additional policy aspects may include how to authorize use, prohibited use, perform systems management, handle policy violations, and handle liability issues.

For consistency and clarity, BYOD policy should be integrated with the overall security policy and the acceptable use policy. To help ensure policy compliance and understanding, a user communication and training process should be in place and ongoing.

How are GroundControl software products used with Cambrionix hardware products?

GroundControl takes full advantage of Cambrionix’s powerful APIs for hardware data and user interaction. The hardware/software combination means users can determine that a device is functional, tested, and charged by a simple green LED.

If anything is wrong with the device, tap GroundControl’s “Self Heal” button, and the Cambrionix charge/sync unit will initiate a full wipe and restore of the image.


What is GroundControl and how can it help me manage Apple iOS devices?

GroundControl is a cloud-managed system for automating iOS setup and configuration, so that a single technician can set up dozens of devices at once. GroundControl can dramatically accelerate both simple workflows (securely wipe and test devices for refurbishment) and the most complex (setting dozens of settings and enrolling in DEP and MDM for iPhones for clinical communications).

In certain cases, GroundControl can be fully automated, so that no IT involvement is required to wipe and reprovision devices.


How to switch USB power on and off.

This is a very common question, you need to simply switch off or disable a USB device but don’t want to have to unplug the cable. Thankfully this is easy with Cambrionix products since we offer 3 methods to achieve this:

LiveViewer App:

This is available on our downloads page along with a user guide showing how to use the various features including how to choose which USB ports to turn on or off or into other modes such as charging or sync/data. LiveViewer is a GUI application which runs on Mac or Windows.


The API (Application Programming Interface) can also be found on our downloads page along with a user guide. The API allows you to programmatically change port states, amongst a large number of other features, and is designed such that you can incorporate the features of our hardware products into your own software. This is particularly useful when writing test scripts for USB hardware or performing SQA testing where USB control over attached mobile devices is required.

Command line (Terminal):

We also offer a command line interface which allows you to send commands directly to our hardware over a VCP (Virtual COM Port). Simply open a serial terminal such as ZTerm and connect to our hardware using 115,200 baud 8N1. Once you get a command prompt, type help for a list of commands and their usage.

Can I sync (transfer USB data) without charging?

Due to the requirements of the USB specification (available from USB.org) it is not possible to maintain a data connection to a USB device without the presence of the USB VBUS voltage.

With interfaces such as a UART, and many other serial data interfaces, it is possible to simply connect the data signals along with a reference-level signal (typically 0V or GND) and still be able to transfer data perfectly well. With USB, VBUS (5V from the host cable) must be connected to the downstream device even if it is self-powered.


To start the USB connect process on host side, the downstream device must pull-up D+ (in case of Full-Speed/High-Speed mode), or D- (for a Low-Speed device).

However, the USB specification has a mandatory requirement that no USB device should source any current on any interface pin unless it is connected to a cable and in turn connected to a host, see section, which reads:

The voltage source on the pull-up resistor must be derived from or controlled by the power supplied on the USB cable such that when VBUS is removed, the pull-up resistor does not supply current on the data line to which it is attached.

So, in summary, no it is not possible to transfer USB data without the presence of USB VBUS. It may be possible with modified downstream device hardware but this is outside of the scope of this document.

The USB2.0 Specification can be found at USB.org.

Is it possible to Sync (or transmit USB data) whilst charging my devices?

Yes…and no, it depends on the device manufacturer.

Most modern mobile devices support charging alongside data transfer, some older devices don’t.

Cambrionix products will always offer the mobile device enough power to charge at high speed whether it is transferring data or not. The power is there for the connected device and some will take the additional power for charging and some wont. It depends on what charging profile the connected device supports.

If we place one of our USB ports into ‘charging’ mode then things are a little different and at that point we use the USB data lines to signal to the connected device that we are a charger and can supply ‘x’ current. There is actually much more to it than that but in essence we let the device know that we aren’t a standard USB port. When we place a port in ‘charging’ mode, because we utilise the data lines, USB data (or Sync) is not possible.

A standard USB port (ie. not a Cambrionix product) only offers 500mA. This is the maximum amount of current which a connected device can assume is available. This is why some older devices will only charge at 500mA when connected to a host computer.

When we place one of our ports in ‘sync’ mode, the connected device (if it supports BC1.2 CDP or other suitable charging profiles) will start charging. We can even simultaneously charge and sync older 30pin Apple devices using our ChaSync software which is available in our downloads section.

So, in summary, some devices can and some can’t and its difficult to determine without testing the actual device. Most modern devices will at least charge at a rate above 500mA (typically up to 1.5A if BC1.2 CDP is supported) when transferring USB data and some Apple devices can even exceed this.

Cambrionix devices typically support: Apple, Samsung, SDP, CDP, DCP, BC1.x, SE1, ACA-x, YD/T-1591, RIM, and many more charger profiles. We can also add more as they become available via our upgradeable firmware and Updater App.

Read more about BC1.2 in this PDF guide.

Are Cambrionix products compatible with Mobile Device Management (MDM) software?

All Cambrionix managed-USB products are compatible with MDM software, regardless of the developer.

All Cambrionix managed-USB products are compatible with all mobile devices, regardless of manufacturer or operating system (OS). This ensures that any BYOD (Bring Your Own Device) initiative will run smoothly for users within your organisation.

Because of the way our products work, they are transparent to the MDM software and the host computer on which the MDM software is running. The host computer simply sees your mobile devices.

Some MDM software has leveraged the advanced features of our products such as our API, which allows port control, hardware LED control and high speed charging for connected USB devices.

Currently, we are compatible with all Mobile Device Management (MDM) software packages including:

GroundControl – GroundControl use our advanced features and API to provide an intuitive user experience when used with some Cambrionix products.

Mobile Heartbeat – Mobile Heartbeat is aimed at the Healthcare market and offers a number of secure communications benefits for clinicians.


IBM MaaS360


Citrix XenMobile

There are some useful PDF guides which you can download below.

CIO Guide to building an MDM strategy

What is MDM software

Is USB Type-C Faster than USB2.0 or USB3.0?

Not necessarily!

USB has been around as a specification for a long time, its evolved over the years and there are now a number of USB connectors and data transfer standards available.

USB Type-C is simply a specification for a connector type.

The USB Type-C connector is unique in that it can be reversed (unlike a standard USB-A, USB-B or Micro-USB), a lot like the Apple Lightning connector. It also has a number of extra pins to allow USB2.0, USB3.0 and USB3.1 to be transferred across the cable. You can also transfer Thunderbolt 2, Thunderbolt 3, DisplayPort and Ethernet across an appropriate cable mated with a Type-C connector but thats beyond the scope of this FAQ.

So, the answer to this FAQ is that yes, a Type-C connector can be used with all kinds of high-speed data standards which are faster than USB2.0 or USB3.0 but they all rely on an appropriate cable and host-computer compatibility. Just because there is a USB Type-C port on a device, its doesn’t mean it offers data speeds in excess of USB2.0!

More information on USB Type-C can be found here under our ‘What is USB Type-C’ FAQ.



usb type-c

What is USB Type-C and what are the main features?

The content of this FAQ article is based upon Wikipedia entry:


The full Wikipedia article is available here.


USB Type-C, commonly known as simply USB-C, is a 24-pin USB connector system allowing transport of data and power. It is distinguished by its horizontally symmetrical “reversible” connector.

The USB Type-C Specification 1.0 was published by the USB Implementers Forum (USB-IF) and was finalized in August 2014. It was developed at roughly the same time as the USB 3.1 specification.

A device that implements USB-C does not necessarily implement USB 3.1, USB Power Delivery, or Alternate Mode.


USB type C USB-C type c


The USB-C connectors connect to both hosts and devices, replacing various USB-B and USB-A connectors and cables with a standard meant to be future-proof. The 24-pin double-sided connector is slightly larger than the micro-B connector, with a USB-C port measuring 8.4 millimetres (0.33 in) by 2.6 millimetres (0.10 in). The connector provides four power/ground pairs, two differential pairs for non-SuperSpeed data (though only one pair is populated in a USB-C cable), four pairs for SuperSpeed data bus (only two pairs are used in USB 3.1 mode), two “sideband use” pins, VCONN +5 V power for active cables, and a configuration pin used for cable orientation detection and dedicated biphase mark code (BMC) configuration data channel.

Connecting an older device to a host with a USB-C receptacle requires a cable or adapter with a USB-A or USB-B plug or receptacle on one end and a USB-C plug on the other end. Legacy adapters with a USB-C receptacle are “not defined or allowed” by the specification because they can create “many invalid and potentially unsafe” cable combinations.


Devices may be hosts or peripherals. Some, such as mobile phones, can take either role depending on what kind is detected on the other end. These types of ports are called Dual-Role-Data (DRD). When two such devices are connected, the roles are randomly assigned but a swap can be commanded from either end. Furthermore, dual-role devices that implement USB Power Delivery may independently and dynamically swap data and power roles using the Data Role Swap or Power Role Swap processes. This allows for charge-through hub or docking station applications where the Type-C device acts as a USB data host while acting as a power consumer rather than a source.

USB-C devices may optionally provide or consume bus power currents of 1.5 A and 3.0 A (at 5 V) in addition to baseline bus power provision; power sources can either advertise increased USB current through the configuration channel, or they can implement the full USB Power Delivery specification using both BMC-coded configuration line and legacy BFSK-coded VBUS line.


USB-C 3.1 cables are considered full-featured USB-C cables. They are electronically marked cables that contain a chip with an ID function based on the configuration channel and vendor-defined messages (VDM) from the USB Power Delivery 2.0 specification. Cable length should be ≤ 2 m for Gen 1 or ≤ 1 m for Gen2. Electronic ID chip provides information about product/vendor, cable connectors, USB signalling protocol (2.0, Gen1, Gen 2), passive/active construction, use of VCONN power, available VBUS current, latency, RX/TX directionality, SOP controller mode, and hardware/firmware version.

USB-C 2.0 cables do not have shielded SuperSpeed pairs, sideband use pins, or additional wires for power lines. Increased cable lengths up to 4 m are possible.

All USB-C cables must be able to carry a minimum of 3 A current (up to 60 W @20V) but can also carry high-power 5 A current (up to 100 W). All USB-C to USB-C cables must contain e-marker chips programmed to identify the cable and its current capabilities. USB Charging ports should also be clearly marked with capable power wattage.

Full-featured USB-C cables that implement USB 3.1 Gen 2 can handle up to 10 Gbit/s data rate at full duplex. They are marked with a SuperSpeed+ (SuperSpeed 10 Gbit/s) logo. There are also cables which can carry only USB 2.0 with up to 480 Mbit/s data rate. There are USB-IF certification programs available for USB-C products and end users are recommended to use USB-IF certified cables.


Audio Adapter Accessory Mode

USB-C plug supports analog headsets through an audio adapter accessory with a 3.5 mm socket providing four standard analog audio signals (Left, Right, Mic, and GND). The audio adapter may optionally include a USB-C pass-through plug to allow 500 mA device charging. The engineering specification states that a 3.5 mm analog headset jack should not replace a USB-C plug.

Analog signals use the USB 2.0 positive differential pair (Dp) and the two side-band use pairs. The presence of the audio accessory is signalled through the configuration channel and VCONN.

Alternate Mode

An Alternate Mode dedicates some of the physical wires in a USB-C 3.1 cable for direct device-to-host transmission of alternate data protocols. The four high-speed lanes, two side-band pins, and (for dock, detachable device and permanent cable applications only) two non-SuperSpeed data pins and one configuration pin can be used for alternate mode transmission. The modes are configured using vendor-defined messages (VDM) through the configuration channel.


USB Type-C Specification – 1.0 Connector pinouts

Type-C plug and receptacle pinouts
Pin Name Description Pin Name Description
A1 GND Ground return B12 GND Ground return
A2 SSTXp1 SuperSpeed differential pair #1, TX, positive B11 SSRXp1 SuperSpeed differential pair #2, RX, positive
A3 SSTXn1 SuperSpeed differential pair #1, TX, negative B10 SSRXn1 SuperSpeed differential pair #2, RX, negative
A4 VBUS Bus power B9 VBUS Bus power
A5 CC1 Configuration channel B8 SBU2 Sideband use (SBU)
A6 Dp1 Non-SuperSpeed differential pair, position 1, positive B7 Dn2 Non-SuperSpeed differential pair, position 2, negative[a]
A7 Dn1 Non-SuperSpeed differential pair, position 1, negative B6 Dp2 Non-SuperSpeed differential pair, position 2, positive[a]
A8 SBU1 Sideband use (SBU) B5 CC2 Configuration channel
A9 VBUS Bus power B4 VBUS Bus power
A10 SSRXn2 SuperSpeed differential pair #4, RX, negative B3 SSTXn2 SuperSpeed differential pair #3, TX, negative
A11 SSRXp2 SuperSpeed differential pair #4, RX, positive B2 SSTXp2 SuperSpeed differential pair #3, TX, positive
A12 GND Ground return B1 GND Ground return

USB Type-C receptacle pinout end-on view

USB Type-C plug pinout end-on view

Cable wiring

Full-featured USB 3.1 and 2.0 Type-C cable wiring
Plug 1, USB Type-C USB Type-C cable Plug 2, USB Type-C
Pin Name Wire colour No Name Description 2.0 Pin Name
Shell Shield Braid Braid Shield Cable external braid Shell Shield
A1, B12,
B1, A12
GND Tin-plated 1 GND_PWRrt1 Ground for power return A1, B12,
B1, A12
16 GND_PWRrt2
A4, B9,
B4, A9
VBUS Red 2 PWR_VBUS1 VBUS power A4, B9,
B4, A9
B5 VCONN Yellow 18 PWR_VCONN VCONN power, for active cables B5 VCONN
A5 CC Blue 3 CC Configuration channel A5 CC
A6 Dp1 White 4 UTP_Dp Unshielded twisted pair, positive A6 Dp1
A7 Dn1 Green 5 UTP_Dn Unshielded twisted pair, negative A7 Dn1
A8 SBU1 Red 14 SBU_A Sideband use A B8 SBU2
B8 SBU2 Black 15 SBU_B Sideband use B A8 SBU1
A2 SSTXp1 Yellow 6 SDPp1 Shielded differential pair #1, positive B11 SSRXp1
A3 SSTXn1 Brown 7 SDPn1 Shielded differential pair #1, negative B10 SSRXn1
B11 SSRXp1 Green 8 SDPp2 Shielded differential pair #2, positive A2 SSTXp1
B10 SSRXn1 Orange 9 SDPn2 Shielded differential pair #2, negative A3 SSTXn1
B2 SSTXp2 White 10 SDPp3 Shielded differential pair #3, positive A11 SSRXp2
B3 SSTXn2 Black 11 SDPn3 Shielded differential pair #3, negative A10 SSRXn2
A11 SSRXp2 Red 12 SDPp4 Shielded differential pair #4, positive B2 SSTXp2
A10 SSRXn2 Blue 13 SDPn4 Shielded differential pair #4, negative B3


  1. Notes:
  2. USB 2.0 Type-C cables do not include wires for SuperSpeed or Sideband use.
  3. VCONN must not traverse end-to-end through the cable. Some isolation method must be used.
  4. There is only a single differential pair for non-SuperSpeed data in the cable, which is connected to Wire colours for differential pairs are not mandated.

Connector pin usage in different modes

USB 2.0/1.1

A simple USB 2.0/1.1 device mates using one pair of D+/D- pins. Hence, it does not require any connection management circuitry, and therefore USB-C is backward compatible with even the oldest USB devices. VBUS and GND provide 5 V up to 500 mA of power.

USB Power Delivery

USB Power Delivery uses one of CC1, CC2 pins for power negotiation up to 20 V at 5 A (or whatever less the source can provide). It is transparent to any data transmission mode, and can therefore be used together with any of them.

USB 3.0/3.1/3.2

In the USB 3.0/3.1/3.2 mode, two or four high speed links are used in TX/RX pairs to provide 5 to 20 Gbps throughput. One of the CC pins is used to negotiate the mode.

VBUS and GND provide 5 V up to 900 mA, in accordance with the USB 3.1 specification. A specific USB-C mode may also be entered, where 5 V up to 3 A is provided. A third alternative is to establish a Power Delivery contract.

The D+/D- link for USB 2.0/1.1 is typically not used when USB 3.x connection is active, but devices like hubs open simultaneous 2.0 and 3.x uplinks in order to allow operation of both type devices connected to it. Other devices may have fallback mode to 2.0, in case the 3.x connection fails.

Alternate Mode

In the Alternate Mode one up to four high speed links are used in whatever direction is needed. SBU1, SBU2 provide an additional lower speed link. If two high speed links remain unused, then a USB 3.0/3.1 link can be established concurrently to the Alternate Mode. One of the CC pins is used to perform all the negotiation. An additional low band bidirectional channel (other than SBU) may share that CC pin as well. USB 2.0 is also available through D+/D- pins.

In regard to power, the devices are supposed to negotiate a Power Delivery contract before an alternate mode is entered.

Analog Audio Out & Microphone

The purpose of this mode is to replace the 3.5 mm headphone jack, from devices like smartphones and tablets, with the thinner USB-C jack. It is supposed to operate only with an adaptor: USB-C plug to headphone jack, so manufacturers are not supposed to market analog headsets with a USB-C plug instead of a headphone plug. This mode is totally separate from digital audio through USB, which typically would use the USB 2.0 mode.

In this mode, all digital circuits are disconnected from the connector, and certain pins become reassigned for analog outputs or inputs. The mode, if supported, is entered when both CC pins are shorted to GND. D- and D+ become audio output left L and right R, respectively. The SBU pins become a microphone pin MIC, and the analog ground AGND, the latter being a return path for both outputs and the microphone. Nevertheless, the MIC and AGND pins must have automatic swap capability, for two reasons: firstly, the USB-C plug may be inserted either side; secondly, there is no agreement, which TRRS rings shall be GND and MIC, so devices equipped with a headphone jack with microphone input must be able to perform this swap anyway.

This mode also allows concurrent charging of a device exposing the analog audio interface (through VBUS and GND), however only at 5 V and 500 mA, as CC pins are unavailable for any negotiation.

Related USB-IF specifications

As outlined by the USB Type-C Cable and Connector Language Usage Guidelines, if a product implements USB Type-C, it does not necessarily implement USB 3.1 or USB Power Delivery.

USB 2.0 Billboard Device Class specification

USB 2.0 Billboard Device Class is defined to communicate the details of supported Alternate Modes to the computer host OS. It provides user readable strings with product description and user support information. Billboard messages can be used to identify incompatible connections made by users. They are not required to negotiate Alternate Modes and only appear when negotiation fails between the host (source) and device (sink).

USB Audio Device Class 3.0 specification

USB Audio Device Class 3.0 defines powered digital audio headsets with a USB-C plug.

Alternate Mode partner specifications

As of 2016 four system-defined Alternate Mode partner specifications exist. Additionally, vendors may support proprietary modes for use in dock solutions.

List of Alternate Mode partner specifications
Name Date Protocol
DisplayPort Alternate Mode published in September 2014 DisplayPort 1.3
MHL Alternate Mode announced in November 2014 MHL 1.0, 2.0, 3.0 and superMHL 1.0
Thunderbolt Alternate Mode announced in June 2015 Thunderbolt 3 (includes DisplayPort 1.2 Alternate Mode)
HDMI Alternate Mode announced in September 2016 HDMI 1.4b

Other serial protocols like PCI Express and Base-T Ethernet are possible.

Alternate Modes are optional USB Type-C features and devices are not required to support any specific Alternate Mode. The USB Implementers Forum is working with its Alternate Mode partners to make sure that ports are properly labelled with respective logos.

Alternate Mode hosts and sinks can be connected with either regular full-featured USB-C cables, or converter cables/adapters:

USB 3.1 Type-C to Type-C full-featured cable
DisplayPort, MHL, HDMI and Thunderbolt (20 Gbit/s) Alternate Mode USB-C ports can be interconnected with standard passive full-featured USB Type-C cables. These cables are only marked with standard “trident” SuperSpeed USB logo (for Gen 1 cables) or the SuperSpeed USB 10 Gbit/s logo (for Gen 2 cables) on both ends. Cable length should be 2.0 m or less for Gen 1 and 1.0 m or less for Gen 2.
USB 3.1 Type-C to Type-C active cable
Thunderbolt 3 (40 Gbit/s) Alternate Mode requires active USB Type-C cables that are certified and electronically marked for high-speed ThunderBolt 3 transmission, similarly to high-power 5 A cables. These cables are marked with standard “trident” SuperSpeed 10 Gbit/s logo and a Thunderbolt logo on both ends.
USB 3.1 Type-C adapter cable (plug) or adapter (socket)
These cables/adapters contain a valid DisplayPort, HDMI, or MHL plug/socket marked with the logo of the required Alternate Mode, and a Type-C plug with a “trident” SuperSpeed 10 Gbit/s logo on the other end. Cable length should be 0.15 m or less.

Active cables/adapters contain powered ICs to amplify/equalise the signal for extended length cables, or to perform active protocol conversion. The adapters for video Alt Modes may allow conversion from native video stream to other video interface standards (e.g., DisplayPort, HDMI, VGA or DVI).

Using full-featured USB-C cables for Alternate Mode connections provides some benefits. Alternate Mode does not employ USB 2.0 lanes and the configuration channel lane, so USB 2.0 and USB Power Delivery protocols are always available. In addition, DisplayPort and MHL Alternate Modes can transmit on one, two, or four SuperSpeed lanes, so two of the remaining lanes may be used to simultaneously transmit USB 3.1 data.

Alternate Mode protocol support matrix for USB 3.1 Type-C cables, adapter cables and adapters
Mode Type-C cable[nb 1] Adapter Construction
USB[nb 2] DisplayPort Thunderbolt superMHL HDMI HDMI DVI-D Component video
3.1 1.2 1.3 20 Gbit/s 40 Gbit/s 1.4b 1.4b 2.0b single-link dual-link (YCbCr, VGA/DVI-A)
DisplayPort Yes Yes   No Passive
Optional Optional Yes Yes Yes Active
Thunderbolt Yes Yes   Yes Yes[nb 3]   No Passive
Optional Optional Optional Yes Yes Yes Yes Active
MHL Yes   Yes   Yes No Yes No No Passive
Optional Optional   Yes   Yes Active
HDMI   Yes Yes No Yes No No Passive
Optional   Yes Active
  1. nb_1: USB 2.0 and USB Power Delivery are available at all times in a Type-C cable
  2. nb_2: USB 3.1 can be transmitted simultaneously when the video signal bandwidth requires two or fewer lanes
  3. nb_3: Thunderbolt 3 40 Gbit/s Passive cables are only possible <0.5m due to limitations of current cable technology.

Software support

  • Linux has supported USB 3.0 since kernel version 2.6.31 and USB version 3.1 since kernel version 4.6.
  • Windows 10 and Windows 10 Mobile support USB 3.1, USB-C, alternate modes, billboard device class, power delivery, audio accessory, and USB Dual-Role support.
  • Windows 8.1 added USB-C and billboard support in an update.
  • OS X Yosemite supports USB 3.1, USB-C, alternate modes, and power delivery.
  • Android Marshmallow works with USB 3.1 and USB-C.
  • Chrome OS supports USB 3.1 and USB-C starting with the Chromebook Pixel 2015 and supports alternate modes, power delivery, and USB Dual-Role support.

Power issues with non-compliant accessories

Some non-compliant cables with a USB-C connector on one end and a legacy USB-A plug or Micro-B receptacle on the other end incorrectly terminate the Configuration Channel (CC) with a 10kΩ pullup to VBUS instead of the specification mandated 56kΩ pullup, causing a device connected to the cable to incorrectly determine the amount of power it is permitted to draw from the cable. Cables with this issue may not work properly with certain products, including Apple and Google products, and may even damage power sources such as chargers, hubs, or PC USB ports.

ThunderSync – How to add extra ports using PP15S (PowerPad15S)

The ThunderSync Thunderbolt to Managed-USB bridge can be daisy chained to add additional ports. This means connecting multiple ThunderSync’s together using Thunderbolt cables. This may not always be suitable for your application.

Another alternative, to add extra downstream USB ports, would be to use a combination of ThunderSync’s and PowerPad15S products.

Because of the internal architecture of ThunderSync, there is an optimum method to connect the PowerPad15S products to ThunderSync to ensure you get the best data transfer speed possible.

This PDF guide describes how to connect multiple PowerPad15S products to ThunderSync.

U16S PSU – How to adjust the power supply to output 5.2V

In order for the U16S (and U8S) modules to work correctly they require a voltage input of 5.2V.

Typically, off the shelf industrial power supplies offer a 5V output but have an adjustment screw which gives some level of adjustment on the voltage output.

If the power supply is not adjusted to 5.2V there may be scenarios where the U16S will detect a low voltage at its input and shutdown, you may also experience lower speed charging for connected devices.

*PSU adjustment should be performed by a qualified and competent electrical engineer and appropriate safety testing should be performed once installed into your finished product*

The PDF guide here shows how to adjust the power supply in a safe manner.

How do I daisy-chain / connect multiple PowerPad15 products together

The PowerPad15S is an extremely versatile managed-USB hub with intelligent charging. It has 15 downstream USB charging and data ports and a single upstream host port.

If more than 15 downstream USB ports are required, you will need to either connect multiple PowerPad15S products to separate USB ports on your host computer or connect multiple PowerPad15S products together.

The process of connecting them together is called daisy-chaining and the guide here shows how to do this.

The same method is used with the PowerPad15C and SuperSync15 too.

Why do Amps matter? or.. Why doesn’t my USB device charge properly?

Why do Amps matter?

In this day and age of USB charging it is important, as a customer, to understand why ‘Amps’ matter. It’s beyond the scope of this document to explain what ‘Amps’ are but we will explain why you need to take notice when they are mentioned on charge/sync cart/case specification sheets.

Would you charge your iPad using a Nokia phone charger?  If not, why?  Why does it matter?  

Cambrionix Ltd, Leaders in mobile technology charging and connectivity, have been doing some research into iPad charging devices and how the voltage and current (Amps) effect this.

Current is often a misunderstood concept.  We’ll start off by talking about voltage as it is linked.  Many people know it is important to match voltage of a power supply or charger to the product. The product will often say 5V DC. It is important that 5V DC is applied to the product. If you apply too many volts e.g 12V you will almost certainly destroy the product! If you apply too little the product won’t work. If you think of your product as a torch when the batteries are new the torch is nice and bright because they are at the correct voltage. As time goes by the batteries become flat and so the voltage drops and so the torch dims as it is operating at too lower voltage and eventually it will stop working. So the the volts must be correct for a product to work.

Current is supplied by a power supply or charger. A product (e.g an iPhone/iPad) consumes current. It will try and take as much current as it needs. So if a product requires 2.1Amps then the power supply should be able to supply 2.1Amps or more. If the power supply can supply more than 2.1Amps this doesn’t matter as the product will only take 2.1Amps. If the power supply can only supply 1 Amp in this case then either the product will fail to work/charge or charge slowly as it can’t get enough current (or power) to charge the battery. So here charging will take twice as long.

So it is important to match voltage between the charger and device. It doesn’t matter if the power supply / charger can provide more current then the device requires. Providing less current will prevent charging or slow it down the same as a poorly designed charger can also prevent charging or slow it down. Unfortunately, testing for a poorly designed charger requires test equipment that, typically, only electronics labs have. So it is important to use reputable manufacturers.

As an example, an iPad requires a charger which is capable of supplying 2.1Amps at a voltage of no less than 4.97V at the charger connector (when the iPad is connected and charging). Failure to supply this amount of current at the right voltage will extend the amount of time required to charge the iPad battery. This detrimental effect can be easily demonstrated by charging an iPad, from empty to full, with an iPhone charger. An iPhone charger can only supply the iPad with 1Amp (referred to as ‘1A’ on most product spec-sheets) so charging times are increased dramatically! This becomes a problem if your iPads cannot be charged in time for their next use (for example, placed on charge at 5pm and not charged by 8am the next day!).

So, in summary, always read the small print and spec-sheet when purchasing charging devices or sync/charge devices and ensure that you are charging at the correct rate for the tablet device you are using.

All Cambrionix sync/charge components offer the correct charging current and voltage to the connected iPads ensuring charging is completed in the fastest possible manner.


How do I connect multiple ThunderSync16 Thunderbolt to USB products together to create more USB ports?

ThunderSync16 is a great product offering a fast Thunderbolt 2 host interface and 16 high-speed managed-USB downstream ports for devices such as the Apple iPad, Android tablets etc. Occasionally, there is a need for more than 16 ports which means that you have 2 options:

  • Connect 2 ThunderSync16 products to a single host (this assumes that the host has 2 Thunderbolt 2 ports available).
  • Daisy-chain 2 ThunderSync16 products together using the expansion/daisy-chain ports built right into ThunderSync16 itself.

This PDF guide shows how to connect multiple ThunderSync16 products together to achieve downstream port counts much higher than 16.

How do I connect a number of 8 port U8S managed-USB modules together to create more ports?

The U8S managed-USB OEM module can be used to create systems with large numbers of downstream USB ports far in excess of the 8 ports already provided.

Connecting multiple U8S OEM modules together is slightly more difficult than performing the same task with U16S OEM modules. This is due to the U8S having a separate ‘control port’ for monitoring and control of the 8 downstream USB ports. What this means is that there are 2 USB cables between each U8S OEM module rather than 1.

The PDF guide here outlines how to connect multiple U8S OEM modules together in a ‘daisy-chain’

Connecting multiple EtherSync USB hubs together

The EtherSync network-attached USB hub can be connected to other EtherSync modules very simply using a Gigabit Ethernet cable and you can connect many EtherSync’s together to create more, remotely managed, network-connected, downstream USB ports.

This is made possible because EtherSync contains a built-in 2 port Gigabit Ethernet switch.

The PDF outlines how to connect multiple EtherSync and what cables are required.

How do I connect multiple U16S modules using the expansion port?

The U16S OEM USB Module can be connected to other U16S modules quickly and easily and you can connect as many as 5 U16S together via the expansion port. We call this process ‘daisy-chaining’.

The PDF guide here outlines how to do this and what cables are required.