[SOLVED] USB input to an audio amplifier

Hi, I have build an small audio amplifier with LM 386 with 8ohm speaker. Now i want to connect a usb jack to its input. so that i load usb with music and amplifier starts playing music! but i dont have any idea how to do it ..Any help would be greatly appreciated. Plz help!!

Well, that's quite a jump. USB is a digital communications system and audio is, well, audio. You need a LOT of hardware and software between your USB connector and your amplifier.

You need a LOT of hardware and software between your USB connector and your amplifier.

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That's true. But a single USB DAC chip with a few additional passive components can do, e.g. TI PCM270x.

I think the OP wants to plug in a USB flash drive and play music from it, rather than plug into a PC as a sound device.

Even more work to do...

Even more work to do...

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Yes, I think you're right. There are no ready-to-use chips for this purpose, because the individual user interface (the "software") is a considerable part of the product design. Everyone would refer to a MP3 player from the market around the corner.

i have some circuits for usb audio

matthai said:

i have some circuits for usb audio

View attachment 81829

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Yup, that looks simple enough.

barry said:

Yup, that looks simple enough.

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Yeah, and I bet the software is a piece of cake :???: :lol:

Thanx guys... I think i need some more experience to do that.

Lol, I would need more experience myself to do that!

If you want some simpler, but still good fun, ideas:

Buy a really cheap MP3 player from the evilbay, take it apart and build it into a small box with your amplifier (better yet, make a stereo amp) and speaker and some nicer control buttons.

Get an old computer CD-ROM drive that has a 'play' button on the front as well as eject, connect it to a power supply and connect your amplifier (again stereo would be nice) to the CD-ROM's audio output. I used such a set up for a few years for playing my CD's. No PC required! You could add that to the above MP3 player (but the CD-ROM will only play normal audio CD's of course). A more advanced version of this uses a Micrchip PIC to control the CD-ROM and allow more flexibility than just 'play'.

Or, if you are into PC stuff, the TI PCM270x integrated circuits that FvM mentioned are a very easy way to make your own USB-connected sound 'card' for your PC, along with your amp again. A little more involved than the LM386 wiring, and some fine soldering of the chip itself, but it really is not hard to do. Windows even recognizes it without needing to load a driver.

Whatever, we are always here to offer help.