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45W USB Type-C charging adapter control board


The 45W USB Type-C charging adapter control board implements the controls for a charging adapter for a USB Type-C enabled device.

Hardware Capabilities

This board provides the following features, to enable USB Type-C based power charger design:
  • BMC (Biphase Mark Coding) used for USB PD (Power Delivery) communication over the CC wire
  • Support 20V/12V/5V@ 2.25A and up to 45W
  • Support OCP (Over Current Protection) / OVP (Over Voltage Protection) at adapter's secondary side

For schematic, see the attached file at the bottom of this page.

Firmware Source Code

The firmware is located In the Chromium Embedded Controller repository under board/zinger/ :

Building Firmware

Within your Chromium OS chroot, the syntax is:
cd ~/trunk/src/platform/ec
make BOARD=zinger

Flashing Firmware

The firmware is normally flashed via the kernel, as part of the Chrome OS Auto-Update process. Payloads are located in /lib/firmware/cros-pd.

When the adapter is connected to a Chrome device, you can manually flash the read-write firmware as follows:
ectool --cros_pd flashpd 4 <port> /tmp/

The device must be in developer mode to run the ectool command. After running this command, the firmware is located in ~/trunk/src/platform/ec/build/zinger/ec.bin
Sanjay Krishnan,
Jul 23, 2015, 3:30 PM