Question: I am using ESP32 and I used a NPN transistor to allow the

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Question:

I am using ESP32 and I used a NPN transistor to allow the WS2812’s to get a 5V signal from the 3.3V ESP32… but the output that is going to the first LED is inverted, and I need FASTLED library to invert the signalling…

RichardS

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I’m not sure there’s a way to do that.
The recommended level shifter is the SN74HCT245N.

Some interesting test results here:
http://happyinmotion.com/?p=1247

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You might need a PNP transistor to make this work because you need it to be a “high side” switch (in the circuit between VCC and the strip)

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@Sam_Guyer Simply so it does not invert? or is there anyother reason?

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@marmil Last week I saw a post on what to do software wise… now I can not find it :frowning:

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Can you describe a bit more what you can’t find/are looking for?

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@Richard_Sloan Yes. I believe that the circuit you made is an inverter (you see this kind of thing in a textbook on electrical engineering). Can you show a diagram of your circuit?

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Post a picture of your circuit. I’m really a software guy, but there are electrical engineers here who can probably help you.

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This NPN should do the job

Series resistor in Base appr. 1 - 2.2 KOhm

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arrange it as common base amplifier; tie the base to 3.3V, then drive the emitter. http://everycircuit.com/circuit/5712787434373120 everycircuit.com - EveryCircuit - Level shift 3.3V to 5V
you won’t be able to make a transistor switch at 800kHz as a common emitter amplifier without some serious drive current.