PM I2C Drive strength Issue

Autonomous Machines Jetson & Embedded Systems Jetson TX2
1

Hi,

We are using Nvidia TX2 SOM with L4T28.2.1.

ISSUE
We are facing an issue in PM I2C.

ISSUE Description
We are connecting Temperature sensor with PM I2C. We facing an I2C error while reading the temperature value at atmosphere temperature 7-8*C.

For testing purpose we have changed the temperature sensor from PM I2C to GEN I2C and tested the same. In this condition temperature sensor is working fine in (-25C to 25C).

We doubt drive strength of the PM I2C might be the reason for the issue. While surfing the datasheet we came across the registers 0X0C30202C and 0X0C302034.

We updated our results below,

Register Address 0X0C30202C   0X0C302034

Default Value 0x00F00100  0x00F00100  I2c Read error at atmosphere temperature 7-8C 
Tested  Value 0x00000000  0x00000000  I2c Read error at atmosphere temperature 7-8C

Can you please suggest the right value or method to increase the drive strength of PM I2C?

Thanks

2

Hi, what’s the I2C address of temperature sensor? There are several devices on PM_I2C module, addresses are 7’h50 and 7’h4C, you can check if any conflict. The drive strength depends on the pull-up value which is 1k ohm in module and strong enough. If no address conflict, you can measure the waveform of signals to check if it is caused by too much load capacitance.