USB Type-C
Make your keyboard future-proof and reversible
Type-C USB
- Slightly wider than MicroUSB connectors. Keep in mind when designing PCBs to fit standard cases.
- Soldering is much more difficult.
- Mini/Micro-USB has 5 pins.
- Type-C has 24.
- Completely surface mount Type-C connectors are impossible to solder by iron.
- Type-C connectors have two rows of pins, one of which exit from below the connector.
- If hand-soldering via iron, choose a hybrid connector with through-hole pins for the under-connector row.
- Type-C connectors often do not extend as far as old Mini-USB connectors do from the edge of a PCB.
- Often, the legs of a Type-C through-hole connector are extremely short (<1mm). Thick PCBs may be difficult to assemble.
Design Considerations
- Type-C is physically larger.
- Type-C requires its own components to function.
- Some Type-C connectors have legs too short for 1.6mm PCBs.
- Assembly costs may increase.
Implementation
- CC pins must be connected to 5.1k pull-down resistors
Diagram by Scorpia.co.uk
https://www.scorpia.co.uk/2016/03/17/using-usb-type-c-on-hobyist-projects/
This diagram breakouts to a header.
Keyboard use
- Pull-down the CC lines
- Use the DP/D+ and DM/D- lines just like any other USB connector
- Connect VBUS and GND like any other USB connector
- It is inferred that the pull-downed CC lines don’t have to be connected to anything else in particular.
Type C High-Current Legacy Devices
From ST’s PDF, it appears possible to draw more current through Type-C:
Sources
https://www.scorpia.co.uk/2016/03/17/using-usb-type-c-on-hobyist-projects/
https://www.mpe-connector.de/index.php?lang=en&menu=16&product_group[]=9&action=Search&id_product=7192
http://www.st.com/content/ccc/resource/technical/document/application_note/group0/a6/91/45/9e/12/a0/4d/42/DM00235987/files/DM00235987.pdf/jcr:content/translations/en.DM00235987.pdf