Questions about powering an LED WS2812B or C


Thread Starter


Hi everyone!

I had an idea:
I am trying to power an LED light, a WS2812B or C. I want to run a 3V board and RTC (real time clock) inside it to power a led at a given time, so i know that i must change the battery for a led and i don't miss LED signal I mean if there is no power in the battery i can miss the light signal!

So, the RTC and board will be powered from CD2032 and the LED from other battery source.

Is it complicated to add the two power sources together like a backup UPS system, if the main CR2032 which powers RTC and board runs out, so it switches to LED power source, so the RTC doesn't stop?

thanks for any help you can give.
It all depends on the capacity of the battery vs the load. For batteries that are not used, life depends on the internal leakage or self-discharge.

The voltage will vary as the battery discharges, and with some batteries the impedance will rise significantly. Each of these behaviors differs depending on the broad type of battery, but even within a battery type (e.g. lead-acid) some are made with the same capacity, but better used for heavier loads for a short time or for lighter loads for longer.

You can isolate the power sources with a diode from each. This method can be used (for example) to use a small, long life battery to power memory while the main batteries are replaced. The diodes prevent one battery from trying to charge the other. The battery with the highest voltage will be used. However, some voltage is lost by the diode.
Yes i understand, I ment the self discharge.. which material/type batteries have less of that self discharge? Yeah, when im thinking about that now, there are a lot of conditions that affect self discharge - 4 example the ambient temperature, right? and in my situation i wont be able to control the ambient temp..

Hmm, i never thought about the neopixel, shure, it will use a power even if not lighted up if put into the chain, simple leds dont do that i heard!

i want to run a 3V board with RTC and 20 LED independent, that will light up very rarely! Main power (some kind of batteries) will power the LEDs and board together with RTC, but the internal RTC will have CR2032 for a backup energy source in case when the main batteries ar changed so the clock doesnt stop!

But i need probably simple led (NOT neopixel) which can show me when its time to change the main batteries!
So i understand the thing that i need to build, that gives the signal for changing power source depends on the battery type i choose and the voltage that will flow through and will be needed to power all this! right?

And in simple words.. i will need a led and what else?