STEMMA QT / Qwiic I2C level shifter breakout for connecting a 5 V microcontroller to 3 V-only I2C devices. Use when the downstream Qwiic/I2C peripheral is not 5 V tolerant.
5V-safe power input
3.3V regulator output, up to 500mA
common ground for power and logic
5V-logic I2C clock input with 10K pullup
5V-logic I2C data input with 10K pullup
level-shifted 3V I2C clock output with 10K pullup
level-shifted 3V I2C data output with 10K pullup
JST-SH 4-pin connector on the 5V logic input side
JST-SH 4-pin connector on the level-shifted 3V logic output side
| Pin | Type | Function | Voltage |
|---|---|---|---|
| VIN5V | Power | 5V-safe power input | 5V |
| 3V | Power | 3.3V regulator output, up to 500mA | 3.3V |
| G | Ground | common ground for power and logic | |
| 5CL | Signal | 5V-logic I2C clock input with 10K pullup | 3-5V logic |
| 5DA | Signal | 5V-logic I2C data input with 10K pullup | 3-5V logic |
| 3CL | Signal | level-shifted 3V I2C clock output with 10K pullup | 3.3V logic |
| 3DA | Signal | level-shifted 3V I2C data output with 10K pullup | 3.3V logic |
| STEMMA QT 5V logic input | Unknown | JST-SH 4-pin connector on the 5V logic input side | |
| STEMMA QT 3V logic output | Unknown | JST-SH 4-pin connector on the level-shifted 3V logic output side |
5V-safe power input
3.3V regulator output, up to 500mA
common ground for power and logic
5V-logic I2C clock input with 10K pullup
5V-logic I2C data input with 10K pullup
level-shifted 3V I2C clock output with 10K pullup
level-shifted 3V I2C data output with 10K pullup
JST-SH 4-pin connector on the 5V logic input side
JST-SH 4-pin connector on the level-shifted 3V logic output side
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