Hi Team,
Our product is a MP3 player which only have one 3.5mm audio jack connector.
This connector take care charger, USB data communication, and audio/mic. So we choose TSU6721 as the switch.
Because 3.5mm audio jack doesn't have ID pin, we pull down 200kohm on ID pin(default charger type1) to avoid floating(no ID status).
We also use register 04h bit7 to recognize if there is VBUS. If there is not have VBUS, we will I2C control switch to audio/mic path.
So we have a condition that would over voltage(VBUS 5V) on MIC pin:
Insert USB cable only, NO adapter------>Detect default ID pin------> CPU via I2C read Interrupt2 04h_Bit.7=0------>control switch to audio path
------->connect adapter 5V on VBUS----->MIC pin still connect to VBUS------->AUDIO MIC pin would over voltage because we can't switch VBUS to OUT pin immediately.
Please kindly help to advice solution for this concern, or any suggestion about our detect process.
Many Thanks
