Introduction

• Who

  • Daniel Puratich Architecture & Management

  • Kenny Na EE Designer

• What

  • A USB-C PD sink where we can select the output voltage with resistors

    • DNP and fitted resistors, should be foolproof 0805s

    • could be STUSB4500 - USB-C PD Sink IC

  • Intent for requesting 24V 65W when debugging https://uwarg-docs.atlassian.net/wiki/spaces/EL/pages/2701197313/RPi+Interface+Rev+C?atl_f=content-tree setup without the full drone

    • should support 12V and 5V as well for testing other boards, configured by soldering different resistors

  • Use a USB-C PD chip and the associated required FETs that are required for negotiation

  • Ideally does not require a microcontroller, due to cost constraints

  • USB-C input connector

  • XT30 output connector

  • don't worry about board area too much but it can be tiny

  • no buck converter

Resources

https://www.youtube.com/watch?v=W13HNsoHj7A&t=615s

https://hackaday.io/project/192576-picopd-usb-c-pd-30-pps-trigger-with-rp2040

https://www.ti.com/interface/usb/type-c-and-power-delivery/products.html#1241=PD%20controller&

https://www.usb.org/usb-charger-pd

Engineering

PD Controller Selection

Main Options

There were a few possible options that were selected from research:

• https://www.digikey.ca/en/products/detail/stmicroelectronics/STUSB4500QTR/9092189

• https://www.digikey.ca/en/products/detail/texas-instruments/TPS25730SRSMR/22147461

• https://www.digikey.ca/en/products/detail/infineon-technologies/CYPD3177-24LQXQT/10238323

• Cheap PMIC + RP2040 (ex. https://www.digikey.ca/en/products/detail/onsemi/FUSB302B10MPX/7356099 + https://www.digikey.ca/en/products/detail/raspberry-pi/SC0914-13/14306010?s=N4IgTCBcDaIEoAUwAYAsyQF0C%2BQ)

Decision Matrix

The TPS25730 was selected for its new model, comprehensive datasheet, relatively low price, and simple implementation.

FET Selection

USB-C

Schematic