MCP4725 DAC
- VIN to board 5V
- GND to board GND
- SCL to board SCL with 2K resistor
- SDA to board SDA with 2K resistor
- VOUT to left mono jack tip
QT Py RP2040
- GND to left mono jack sleeve
- GND to right mono jack sleeve
- A1 to right mono jack tip
The 2K resistors for SCL and SDA keep the incoming logic level at 3.3V, rather than 5V.