Part Number: TUSB1310A
Other Parts Discussed in Thread: TUSB1310
On our project, TUSB1310A is connected and controlled by FPGA. PHY_RESETN pin is driven by FPGA. And it will asserted in many user cases. We found under some condition, the USB PHY is not working, the current waveform we tested on ADDA1P8 and ADDA1P1 is attached. it seems the chip collapse. The current varies in 5K period. And the chip cannot be recovered by reset. We need to repower the board to let the USB PHY chip get back.
After we remove the PHY_RESETN logic, so the USB PHY will not under PHY reset so frequently, the issue not happende.
So the questions are:
1. What does the USB PHY chip do when the current of ADDA1P8 and ADDA1P1 appears like the attchement?
2. What does PHY_RESETN do to USB PHY chip? Why it cause such strange current waveform? Why it cannot be recovered by chip reset?
