Kent,
I haven't opened my 1 year old H4 lately but the led flashes when charging and is on steady once there is a full charge. Pulling the usb cable extinguishes the light.?
... Larry
On Fri., 25 Jun. 2021 at 5:00 p.m., Kent AA6P<kawill70@...> wrote: My NanoVNA-H4 has a FM5324B for the battery charger and 5 volt boost converter circuit. The schematic shows a FM5401. Does anyone know the difference?
The datasheet is not written in English. I'm trying to explain why the charging LED on my NanoVNA-H4 does not turn off at the end of charge. The battery does appear to be charging properly. The LED flashes at very low voltages and is steady on at all other times.
In looking at the datasheets, it looks like pins 2-4 can be configured for several different LED configurations. Both datasheets include a state diagram and the FM5324B appears to have one additional state.
Thanks, Kent
AA6P
