Hello Experts,
My client is using TCA9535 in their wafer testing equipment, and currently, there is an issue with the output port resetting during testing. I need assistance in analyzing the cause;
The specific connection is that each output port is connected to a transistor circuit to control a 1-channel relay switch. The relay is connected to a high-voltage DC voltage of approximately 1400V, controlling the on/off of the voltage for wafer high-voltage testing. During the current testing process, it was found that the chip occasionally experiences a situation where the output signal from the output port disappears, causing the relay to disconnect. Upon reading the chip output status, it was found that the state of the chip output port changed to input, leading to the suspicion that the chip automatically reset. The measured power supply waveform is as follows: the waveform is not very stable, suggesting that a power-on reset may have occurred.
Currently, the customer's high-voltage circuit and TCA9535 control circuit are integrated on a single board. Will the high-voltage signal affect this chip? Currently, the customer has added TVS and capacitors to the chip power supply VCC, but the reset issue has not been significantly improved. I hope you can provide some suggestions. Thank you
