If you want to replace the micro-USB / mini-USB for a USB type C connectors in your projects, look no further! In this post you will see just how simple it is!
The USB Type C connector
The USB Type C connector has 24 pins, and is symmetrical so that the cables can be reversed. In effect USB type C is 12 pins. It uses the traditional USB 2.0 D+/D- signals, and two other differential pairs to reach the speeds commanded by the USB 3.2 standard.
In addition, it has a bunch of control lines to communicate on type of capability and power delivery.
All in all, it is fairly complex. That being said, if you just want to use a USB Type C as a traditional USB 2.0 device, it is fairly easy to do so.
USB Type C connector for USB 2.0 applications
If you would like to use a type C plug to replace your micro-USB/mini-USB plugs, all you need to do is:
- Use a 5.1k pull down resistors on the CC1 line
- Use a 5.1k pull down resistors on the CC2 line
- Use the four traditional USB power and data lines: VBUS, GND, D+ and D-
- Ignore and leave everything else unconnected.
That’s it! It is not more complicated than this!
The easy connector: The 12 pin type C
There are hundreds of USB type C connectors. Most of the full 24 pin connectors are really unfriendly packages. They are very dense making it incredibly hard to reliably solder. The solution to this is to use a reduced pin count type C. Since most of the lines are left unconnected, 24 pins are not needed.
One of the simplest connectors is 12 pins. A good part number is “TYPE-C-31-M-12” manufactured by Korean Hroparts Elec.
The connector has the following pinout:
And this is what it looks like on an actual PCB:
Example: Connecting to a FTDI chip
The schematics below uses a USB-C 12-pin connector, together with a popular FTDI full speed USB to UART chip (FT231XS)
The implementation above is simply the recommended application for a USB 2.0 connector. The only difference? Two 5.1k pull down resistors on the CC1 and CC2 lines of the USB type C receptacle connector.
There is no more good reason to use micro-USB. Replacing it with USB type C costs two resistors, and a little bit more space on a PCB. These trade-offs are totally worth it as the 2.0 original connectivity is slowly fading away. Soon it’ll be a relic of the past akin to serial cables. You’d better move on now!