Author Topic: Picking a transistor.  (Read 2117 times)

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Offline paulca

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Re: Picking a transistor.
« Reply #25 on: August 13, 2019, 05:00:04 pm »
So the options that seem to present themselves are:

* to use small NPN transistors in parallel, so each one is only switching <500mA.  It would mean 12 transistors for 4 strips of RGB.
* bin these silly LEDs and just buy the 12V WS2812s, even though I don't need individual (or groups of 3) addressing, they are much easier to deal with.

I might use these elsewhere and just wire 12V to all the pins (or actually 12V to one and ground to the others).
"What could possibly go wrong?"
Current Open Projects:  3 Channel Audio mixer with DAC, BT, pre-amps and h/phone amp, WS281x LED controller Version 2 5V/5A w/Atmega328, FY6600 Power supply, 5A DC Load (Still!)
 

Online ledtester

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Re: Picking a transistor.
« Reply #26 on: August 13, 2019, 05:28:50 pm »
This Adafruit page suggests using a TIP120 or IRLB8271:

https://learn.adafruit.com/rgb-led-strips/usage

Here's the datasheet for the IRLB8721:

https://cdn-shop.adafruit.com/datasheets/irlb8721pbf.pdf

Looks like it should be able to do at least 1A perhaps even 2A at 3.3V.
 


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