nPM1300 VBUS input current limit OTP configuration

[KN7702]

I'm currently working on configuring the nPM1300 used in our custom board. In the product spec v1.2, it supports 2 USB compliant current limits, IBUS at 100mA and IBUS at 500mA, the default is set to 100mA. 

On our custom board, the nPM1300 VSYS connects to our host microcontroller (nRF5340) and the rest of the peripherals. We measured the inrush current at the start (at VSYS output), it is approximately 200mA. With this setup, we cannot power the system from the beginning just using the USB power source alone because it seems that there is a IBUS current limit at 100mA. It must be powered in conjunction with a battery first, then allows the host to start and configures the IBUS current to greater than default (100mA).  

I have several questions related to that, 

A) Is there a way to permanently change it to 500mA at startup? 

B) Both VBUSINILIM0 and VBUSINILIMSTARTUP indicate "Reset value from OTP...", does it mean there is a ONE TIME PROGRAMMABLE interface we can set so it starts from 500mA? 

[KN7702]

So we have most of our peripherals connected to VSYS, but we have some that are connected to the load switches as well. I believe when the nPM1300 limits its input current, it resets itself and never power up the MCU. Hence, the host never have a chance to configure the nPM1300 to accept a new input current limit. 

The current method of workaround is to supply the system from battery from cold start, where it does not have an input current limit. Once the MCU is powered, I can configure nPM1300 to allow higher input current limit. After that, I can use USB to supply the entire system. 

I will change the power architecture so it supplies the power to the MCU first before enabling the rest of the system. Thanks!