1
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2answers
503 views

Noise when powering headphones amplifier through USB port

This question is actually connected with this one: Getting 1.2V from USB I've successfully connected my FIIO E3 headphones amplifier to USB (so that I don't have to use batteries). But I've notices ...
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6answers
859 views

What's causing this high frequency ripple on the output of my LM317?

I'm using an LM317T to regulate 5V to 3.38V for a microcontroller. R1 is 330 ohms and R2 is 560 ohms. There is no input capacitor and the output capacitor is a 470µF 25V, because I had that value in a ...