ESP32 Forum

Hello everyone,

I’m working on a project using the ESP32-S3 (QFN-56 package) and I’m running into an issue when trying to read sensor data over I²C.

Chip: ESP32-S3

Toolchain: ESP-IDF v5.1

Peripherals: I²C connected sensor (address is detected correctly with i2cdetect)

Problem: My code compiles and runs, but the data I get from the sensor is unstable and sometimes shows random jumps.

I’ve already tried adjusting pull-up resistors and different clock speeds (100kHz vs 400kHz), but the issue still persists.

Has anyone experienced similar behavior on the ESP32-S3? Is there a recommended configuration or workaround for stable I²C reads?

For reference, here’s the ESP32-S3 chip I’m using: ESP32-S3 details
Thanks in advance!

ESP32-S3 internal pull-ups are weak (≈45 kΩ), so you must use external pull-ups. For 3.3 V and short bus length: 2.2k–4.7kΩ is usually best. If the bus is long or noisy, lean towards 2.2kΩ.

The problem most likely isn't with the S3 but with the way your code is interacting with the sensor.