Tool/software:
Hi Sir
We have a question about TPS2549RTE.
When charging a phone via the TPS2549RTE, if the phone is restarted while keeping the USB connection intact, the phone is no longer recognized
(ADB devices fail to detect the phone, and this issue occurs 100% of the time).
here is our customer 's guess
- When a non-complaint phone is attached to USB, the phone will do primary detection, and the TPS2549 will enable a timer.
- If the TPS2549 device cannot detect the enumeration signal in 2 seconds after primary detection, it will discharge VBUS and switch to SDP mode automatically.
- After discharging, the TPS2549 operates in SDP mode, and the non-complaint phone can communicate with the host controller.
- After 2 seconds, the TPS2549 switches back to CDP mode, but the phones responds as if it is attached to an SDP, so it can still communicate with the host controller
