We have a ILPS22QS pressure sensor.
We are getting an occasional i2c error.
On investigation it seems the ILPS22QS sensor is holding the SCL line high during a pressure reading.
I have read through the datasheet and see no functionality that would allow this to happen.
We have observed the pressure sensor holding the i2c scl line high.
This is shown in the below oscilloscope capture.
Yellow = sensor side of i2c SCL series resistor R31
Blue = micro side of i2c SCL series resistor R31
It was suggested it could be manufacturing defect of a bad ground connection, however I do not believe this to be the case as:
During a capture where I saw the SCL line being held high the SDA line wasn't:
- Yellow = micro side of i2c SDA series resistor R34
- Blue = micro side of i2c SCL series resistor R31
- Note the lows start at ~0mV and change to ~416mV about 2/3rd the way through the transaction
Does anyone have insight as to what may be happening?
Most of the time the sensor will recover, I saw at least once where it didn't recover and needed a power cycle.