This repository contains two DIY gadgets to monitor and log USB-C Power Delivery (PD).
Both devices are designed to be easy to build, hackable, and useful for makers who want to explore USB-C PD.

• DIY Power Meter
  Small device with an OLED display showing voltage, current, and power in real time.
  Powered by an STM32 microcontroller.

• PD Logger
  Wi-Fi enabled device based on ESP-01s.
  Logs voltage, current, and power for several hours and serves interactive plots in any web browser.

• USB-C connectors: male on the input side, female on the output side.
• CC & VCONN lines are passed through to handle PD voltage negotiation.
• Shunt resistor (50 mΩ) allows precise current measurement.
• INA219 sensor measures voltage and current via I²C.
• Step-down converter generates 3.3 V from 5–20 V input.
• MCUs: STM32 with OLED display (Power Meter), ESP-01s with Wi-Fi (PD Logger).

• Schematics & PCB files → in this repo (/electronics)
• PCBs manufactured by JLCPCB
• 3D printable cases → in /mechanics
• Firmware → in /software

All production data is included in /electronics so you can order, print, and build your own devices.

• Power Meter: plug between charger and device → read values on the display.
• PD Logger: connect to your local Wi-Fi, then open http://pd-logger.local → see live values.
  • Update interval: 5 seconds
  • Logging capacity: several hours
  • Data download as CSV file
  • Interactive plots for Voltage / Current / Power over time

This project is licensed under the
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) license.

You are free to share and adapt the material, for non-commercial purposes only,
as long as you provide proper attribution and distribute your contributions under the same license.

For details, see the LICENSE file.

• Hackaday CH224K USB PD Decoy project for inspiration