Hi
I want to monitor a lithium bank for high and low voltages (11v and 13.8v at +/- 0.05v accuracy) and alarm (buzzer/led/maybe switch an exterior victron device low).
As this will be powered directly off the bank it needs to be low power to avoid draining the battery. It does not need to sample frequently, save once every 30secs?
Is this suitable for a mote or are there other simpler solutions for the light buzzer functionality?
Also any suggestions on the voltage divider values to have accuracy and lower power without impedance issues?
Thanks!
I'd look around at voltage monitor chips before I throw a microcontroller at this type of task, most of these are very low power, some have push/pull pins for external signaling/alarms. But you'd have to find something that goes up to your needed range.
Quote from: gregcope on September 12, 2021, 04:05:43 AM
Also any suggestions on the voltage divider values to have accuracy and lower power without impedance issues?
Impedance issues? Like? Batteries are DC.
Pick prevision resistors according to the 50mV precision you're after and use Ohm's law which will give you the drain. Stay around a few uA, you can use a 0.1uF capacitor on the ADC pin used to measure the bottom resistor of the divider ladder.