SLVSB64I November 2011 – March 2018 TPS65217
The AC and USB inputs have 90-µA internal current sinks which are used to discharge the input pins to avoid false detection of an input source. The AC sink is enabled when the USB input is a valid supply and the AC voltage (VAC) is less than the detection threshold. Likewise, the USB sink is enabled when the AC input is a valid supply and the USB voltage (VUSB) is less than the detection limit. Both current sinks can be forced OFF by setting the ACSINK and USBSINK bits to 11b. Both bits are located in the PPATH register (address 0x01).
Setting the ACSINK or USBSINK bit to 01b and 10b is not recommended as these settings may cause unexpected enabling and disabling of the current sinks.