RE: MS88SF2 Power Configuration

ovrebekk — Mon, 29 Jun 2020 13:11:33 GMT

I am pretty sure your original summary is correct.

If you are looking for optimal current consumption you should use VDD only, and use an external regulator to get the supply voltage within the legal range of VDD.

If you want to use the USB interface of the nRF52840 then you can use the VDDH line for 5V supply. In this case there might be some current leakage through R1, but the assumption is probably that you are not so worried about current consumption when you are supplying power from the USB interface.

If you have a decent ammeter available (or a power profiler) you could try to power the module through VDDH, and see how high the currents are in active and sleep modes. Compare that to the current draw when running through VDD, and you should get an impression of the difference between the two.

Are you thinking of connecting your LiPo battery directly to VDDH to avoid the need for an external regulator?

Best regards
Torbjørn

RE: MS88SF2 Power Configuration

Monty — Sat, 27 Jun 2020 19:34:41 GMT

Was further checking the docs and noticed that the provided configuration table coincides with the design references to a degree, assuming that R1 and R2 are just short circuits. For example the Config 4 has REG0 and REG1 in DCDC enabled and 5 is on Normal Voltage Mode and REG1 is DCDC enabled. However I didn't notice them selling different configurations, thus maybe there is a way to select the desired configurations using some built-in electronically programmable switch...