ICM-20948 9-axis IMU breakout with ESP32

Supply 3.3 V Bus I2C I2C address 0x68 / 0x69 Measures acceleration, rotation, magnetic field, temperature

Pins and ESP32 wiring

Pin	Role	ESP32 pin	Notes
VIN	Power	3V3	Pin order and labels differ between sellers: check the silkscreen
GND	Ground	GND
SCL	I2C clock (SCL)	D22
SDA	I2C data (SDA)	D21
AD0	Not wired to the ESP32	—	Address select: LOW = 0x68, HIGH = 0x69 (some boards pull it HIGH)
CS	Not wired to the ESP32	—	SPI chip select. Leave unconnected or HIGH for I2C
INT	Interrupt	D35	Interrupt output, optional
FSYNC	Not wired to the ESP32	—	Frame sync. Leave unconnected or tie to GND

Suggested wiring for the 30-pin ESP32 DevKit, avoiding flash, input-only and strapping pins. BoardPilot checks it for you as you wire.

Check it is the real chip

Read register 0x00: a genuine part answers 0xea. BoardPilot does this automatically in “Debug a problem”.

Starter code (Arduino)

#include <Wire.h>

void setup() {
  Serial.begin(115200);
  Wire.begin(21, 22);  // SDA = GPIO 21, SCL = GPIO 22
  Wire.beginTransmission(0x68);
  bool found = Wire.endTransmission() == 0;
  Serial.println(found ? "ICM-20948 9-axis IMU breakout found at 0x68" : "Not found: check power, GND and SDA/SCL");
}

void loop() {}

Sources

TDK InvenSense ICM-20948 datasheet, USER BANK 0 register 0x00 WHO_AM_I (reads 0xEA)
TDK InvenSense ICM-20948 datasheet, I2C slave address b110100X, X = AD0 (0x68 / 0x69); VDD 1.71 to 3.6 V

Try it in 3D in BoardPilot

BoardPilot Part data (JSON)

Part data: CC BY 4.0, free to reuse with credit to BoardPilot.