TPS65224-Q1: AM62A main chip and TPS65224 I2C communication occasionally abnormal

YuWei Wu

Part Number: TPS65224-Q1
Other Parts Discussed in Thread: AM62A7, TPS65224

Tool/software:

Hi，

During the operation of our program, we have observed that the I2C signals sent by the main control chip occasionally experience timeout issues. This problem causes our program to return errors. Preliminary investigation suggests that the waveform generated by the I2C is abnormal

The captured erroneous signal image is as follows.

Actually, the correct signal should be as shown in the figure below.

The main control chip we use is the AM62A7, utilizing the R5 core. Our program runs on the MCU, and the PMIC chip employed is the TPS65224

We initially suspect that the issue originates from the TPS65224. During the ACK phase of the I2C communication process, the TPS65224 fails to release control of the bus in a timely manner. This prevents the main control chip from obtaining bus control, and the entire ACK phase becomes excessively long, ultimately leading to a communication timeout

What are the potential causes of this issue, and can it be resolved by modifying the register configuration?

Thanks,

Yuwei

18 hours ago

0 Katie Pier 15 hours ago

TI__Guru* 78051 points

Hi Yuwei,

One way you can confirm which chip is holding the clock line low, is to put a resistor in series on the clock line and then observing the comms on an oscilloscope - the resistor will make a small voltage divider with the pull-up R for the I2C causing a slightly different low level depending on which side of the comms is pulling the line low - then you can tell which side is doing it. Do you think this is a test you could do? It would help us know whether TPS6522x part or AM62x part is holding the line. This kind of test is described here: https://www.i2c-bus.org/i2c-primer/serial-resistances-and-debugging/

Regards,

Katie

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TPS65224-Q1: AM62A main chip and TPS65224 I2C communication occasionally abnormal