We are using the application example nPM1100 in combination with a nRF52840 as mentioned in nPM1100_PS_v1.2.pdf on page 39.
The nRF52 and nPM1100 are both connected to USB in the application example, so D+ and D- pins are connected to both nPM1100 and nRF52.
The nRF52 must wait until nPM1100 completes port detection before enabling its USB port, this is 700mS. A nRF52 GPIO is connected to the ISET pin and sets the VBUS current limit after negotiation, 100mA or 500mA.
With this hardware setup, we want to create a “limit set method” of fixed 500mA.
According to DevZone, setting the ISET pin to high and allowing 500 mA all the time is a feasible option, but is not compliant to the battery charging standard.
devzone.nordicsemi.com/.../336737
Normally, for fixed 500mA, on page 16 you can read, ISET = VSYS, D-=AVSS and D+=NC.
But with this example, D+ and D- are both connected to USB.
Question is, can we set ISET pin to high in hardware and allowing 500 mA all the time, while D+ and D- still connected to nRF52?