Hello! What's the recommended way to use setMaxPowerInVoltsAndMilliamps with 100 neopixel leds,

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Hello!

What’s the recommended way to use setMaxPowerInVoltsAndMilliamps with 100 neopixel leds, a feather board, microphone powered by a 3.7V, 2500 mAh battery?

Thanks much!

R

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In my opinion, you don’t need to go full blast, so I’d start off with something like:

set_max_power_in_volts_and_milliamps(3.7, 1000); // 1 amp

Then, I’d try some anmations and work up from there. If it’s a standard 18650, I probably wouldn’t go over 3 amps.

3

I’d simply stick to 1amp (or even less to make it last longer)

I was running 4amp on my led vest (~600pixels) this weekend and found myself turning down the brightness manually because it was still too bright in most circumstances.

4

Thanks for the sound advice.

Here’s a potentially tricky part - the LEDs can be powered by the battery (3.7V) or via USB (5V). Problem is, it’s not quite possible to know for sure whether the board is running out of battery or USB. In this case, would you keep capping at 3.7V, 1000mAh?

5

Because:

  1. It sounded like the board was able to run directly off of the 3.7V battery. If it runs at 5V, then use 5V in your parameters. Oh, and I even prefer the 5V and use 5V USB power banks (with 3.7V batteries inside) for my displays.

  2. 1000mAh to start because we start small and build up from there. I typically don’t go beyond 500mA for my own strips (of up to 40 LED’s).

6

  1. The board (Adafruit Feather m0) does run directly off of the 3.7V but switches to 5V USB power whenever available (and charges the attached battery)

  2. Great advice, thank you!