Hello,
Our customer asked about how TPS25751 liquid detection works. Even though we understand the function in another e2e thread, we still do not know which I2C register is corresponding to whcih waveform event. As I posted my understanding in below, please check and let me know correct register setting.
Hi Toshiro,
Yes, register 0x98, Liquid Detection config is the correct register.
Sleep time : time between the toggling, and can change depending on the Liquid Detected state.
Number of samples: The number of samples taken during every detection cycle. So if #samples is 2, there will be 2^2 = 4 peaks as seen in your capture.
Thresholds: voltage thresholds for liquid detection. If the measured voltage during the sampling is above/below the threshold during the liquid detected/no liquid state, liquid will be detected.
Sample time: the width of a single peak, as you indicated in your capture.
Liquid detection state: indicates if liquid has been detected per the sampling and thresholds set in this register.
Enable Corrosion mitigation: When enabled, disables the power path and disconnects at the Type-C port when liquid is detected. When not enabled, Liquid detection only reports detection and does not disable power path.
Enable Liquid Detection: Enables liquid detection.
Thanks and Regards,
Chris
Hi Toshiro,
Everything looks correct except 4, 4 is the sample time when liquid is detected, so it will be the same part of the waveform as 5, but will be during the "Liquid Detected" state. In the image below, the high pulse and low pulse both assert for the sample time No Liquid.
Thanks and Regards,
Chris
