Story
Breadboard-compatible breakout for the Vangotech V9381 single-phase energy
monitoring ASIC — the upgraded sibling of the V9360, adding SPI alongside
UART for ~10x faster data acquisition. The SPI interface supports clock
speeds up to 10 MHz in FourWire and ThreeWire modes, enabling rapid waveform
capture (~200 ms) and on-board FFT with ESP-DSP.
UART multi-drop addressing (A0/A1 pins) allows up to 4 V9381 devices on a
shared half-duplex bus. Onboard 3.3 V LDO for 5 V USB compatibility.
Open-hardware KiCad design files and an Arduino library with SPI/UART
waveform capture, FFT, and dirty-mode examples (ESP32-S3) are available
on GitHub.
## What's in the box
- 1x V9381 Breakout PCB (assembled)
- 2x 1x10 pin headers (unsoldered)
## Resources
- Schematic & PCB: https://github.com/whatnick/V93XX_Breakout
- Arduino library: https://github.com/whatnick/V93XX_Arduino
## Technical Specifications
- Supply voltage: 3.3–5 V (onboard LDO)
- Interfaces: UART (half-duplex, 8O1), SPI (FourWire / ThreeWire)
- PCB size: 38.1 × 27.9 mm
- Baud Rates: 1200–19200 bps (auto-baud)
- Spi Clock: 400 kHz–10 MHz
- Supply Voltage: 3.3 V (IC core)
- Chip: Vangotech V9381
- Multi Drop: Up to 4 devices (A0/A1 address pins)
- Form Factor: Breadboard compatible
