Tool/software:
Hello team,
There is a ground short circuit at PIN2 CAP_I2S of the DS90UB948 during production, but customer production line's detection mechanism could not identify this issue, and the INT pin of the 948 was not triggered.
Therefore, we would like to ask which module of the chip is powered by PIN2 CAP_I2S, what are the consequences of this PIN short circuit, such as triggering interrupts, registers, etc. Is there a better method to detect this?
Thanks
Regards
Daniel
Hi Daniel,
The capacitor is placed there to reduce noise on the I2S internal circuits. I would strongly recommend they add the capacitor as shown in our typical applications diagram as it is recommended in our datasheet and can impact the internal mechanism of our device, leading to unexpected behavior.
What is INTB_IN connected to on the 948? INTB_IN is used to detect interrupts from the MCU on the 948 side and propagate that interrupt through the FPD-Link to the serializer, which would then notify the SoC on the serializer side. It's up to the MCU to determine what is considered an interrupt and what is not. In this case, I don't think there is a way to program the MCU to notice there is a hardware difference on the 948.
I would suggest sending in the schematic for review to the BU next time.
BR,
Esther
