We need more USB ports

 

In the pursuit for ever slimmer laptops, manufacturers are removing what appears to be “bulky” USB ports from their new product releases. That may result in a slimmer notebook, but more often than not, individuals end up adding dongles and further bulk so that existing peripherals can still be used.

Mobile developers on our team use the Microsoft Surface Pro 3, and it has been a great laplet for mobile development since most of our software development kits (SDK) and integrated development environment (IDE) run on Windows. It’s compact, feels good, is light (only 800g!), has a touchscreen, and sports a beefy Intel Core i7-4650U processor. It’s perfect. Except for one thing.

It has only one USB port.

Although the single USB port is not yet a widespread design adoption with Windows-based laptop manufacturers, the net was abuzz with gripes surrounding Apple’s design of a single USB-C port on its new range of MacBooks. CNET published an article on some “survival tips”, but it doesn’t hide the fact that sometimes we do need more ports on our computing devices – development kits, Universal asynchronous receiver/transmitters (UART), USB-to-Serial, Bluetooth4.1 dongles, syncing our smartphones and other memory devices. You name it.

A USB hub is an obvious solution. But somehow none of the USB hubs we’ve tried has had the right combination of data-transfer reliability and aesthetics. Cheap hubs with the right profile keep disconnecting our devices, while reliable hubs are expensive.

Is it too hard to ask for a few more USB ports? So we made our own.

Selection of a hub-controller chip is easy, as just about practically every semiconductor manufacturer has a product line of USB hub controllers. Texas Instruments, STMicroelectronics, Cypress, Maxim, Renesas, so on and so forth. Each manufacturer has slight peripheral advantages in its chips over its competitors.

However, a key goal was to keep costs low, which is a good design practice to determine the cost of your Bill of Materials (BOM) before jumping into the design. More often than not, engineers/inventors jump straight into a design and realize far too late that the costs of constructing that particular design reduce the value proposition of the invention or device they are trying to make with marginal improvements over existing solutions.

Consumers are more well-informed when it comes to the selection of products and devices pertaining to their technological tastes and needs, where cost and value are no doubt factors in a decision to purchase.

A quick cursory search revealed Chinese and Taiwanese semiconductor companies producing equivalent USB hub controller chips. Such as Alcor Micro, Genesys Logic, and JFD-IC, FE1.1s which are likely producing the bulk of the world’s original-equipment-manufacturer (OEM) USB-controller chips.

We found Genesys Logic’s GL850G controller chip in one of the hubs lying around the lab. Alcor Micro’s AU6256 and JFD-IC’s FE1.1s also presented attractive options.

As a designer, several factors should be considered.

  1. Does your manufacturer have access to the components that require assembly?
    If it does not, it’s likely that you will have to set up that relationship.
  2. Can you get the necessary components in the volume that you require?
    It’s unlikely that you’ll get 10 pieces from an OEM manufacturer if you cannot commit to a Minimum Order Quantity (MOQ) or sales volume, otherwise you might have to get a more readily available component from a distributor like Future Electronics, Arrow Electronics, Avnet, Digikey, Element14 or Mouser.
  3. Is there a commercial relationship between you and the component provider?
    More often than not, OEM manufacturers from China, Taiwan or South Korea converse in their native languages and cross-border sales teams will face challenges in currency conversions, customs restrictions and/or taxes, and the offset of these hidden costs may render the component more expensive to implement in your design than originally anticipated.

Availability, MOQ, documentation, and cost-per-chip are all factors an engineer has to be aware of during the process of a design. In the end, we selected Standard Microsystems Corporation (SMSC)’s USB2514 USB 2.0 Hi-Speed Hub Controller. SMSC is now owned by Microchip, which means the chip is marketed by a reliable and reputable OEM semiconductor company with established distribution channels.

The USB2514 had a good price of US$1.40 a chip, comprehensive documentation, very minimal BOM and, most importantly, is widely available and accessible to electronic contract manufacturers and assemblers.

Here is our design and the final outcome!

A 3D render of our design

Fabricated, populated and assembled PCB in-house

Top view (male USB headers were soldered on later)

Male headers soldered, and heatshrinked for protection and then distributed to our engineers

Close up

In our opinion, it looks more badass-punkish when its bare electronic guts are exposed. Future design iterations would involve changing the hub to a USB-3.0 controller and possibly include other mechanical features or enclosures, for now, this design works fine and is a talking point when our mobile engineers assist clients on-site. Check out our USB-C “spacedock” design for advanced features that were later added. If you’re interested in making such of a USB hub of your own, we would love to work with you.

Build the future!

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