Other Parts Discussed in Thread: BQ25756, TPS25751
Hello,
I'm using the BQ25756 EVM with the TPS25751 EVM.
-I tested TPS25751 EVM alon and was able to sink and source.
-I tested both togheter in charging mode and it is ok
Finally in reverse operation. the device i connect asks for 20V (small load of 330R (60mA at 20V)) also tested other devices. Results are the same.
5V is sent on Vbus to device for around 1s and then the voltage will drop to 0V the USB_PD will then retry again. And this will go on until i disconnect the device.
From the analysis of the BQ charger : (Ribbon cable between the two devkit is well connected and source supply connected to J3, default jumper locations except TPS25751 supplied from Vbat))
Using Regn to supply Drv_sup, the charger won't wake at all, no regn voltage
Usign external DRV_SUP supply, the charger will have Vregn do three small pulses and then retry later. For the gate signals, it seems like it's doing the compensation check and starts Boost operation for 2ms before it stops.
Any ideas, is there something special to do with devkit to have reverse operation work?
