Tool/software:
Hello,
We use the TPS25751 as a PD controller in our BT audio speaker. One of the features of the product is power bank mode. This means we can configure the unit to either charge its internal battery or charge an external device, such as a phone.
An additional requirement from our UI/UX department is to disable power bank mode if the internal battery level drops below 30%. In this case, we need to adjust the power port to prevent charging external devices.
Here’s what I’ve tried so far:
- Plug in the phone. It starts charging from the unit.
- The battery level drops below 30%.
- The MCU switches the port role from DRP to Sink state machine only.
- The phone switches to source mode and starts charging the unit.
This is incorrect because we only want to stop charging the phone and prevent the phone from switching to the power source role.
Of course, I cannot disable the state machine completely, because MCU should be able to detect and the unit should start charging when we connect it back to the power supply.
Another idea was to set the source current to 0. This way, the phone would remain in sink mode, "charging" from the speaker, but the current would be 0, and we would not lose battery energy.
It would be great if you could provide support and a simple solution to implement this feature.
Thank you!
Best regards,
Anton Glukhov
