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Advice required for audio playback from an IC Answered

Hi All,

I'm new here so go easy on me :)

I need to throw together a circuit to play an MP3 when a switch is closed (Think musical greeting card rather than iPod). 

The fundamental issue is a lack of knowledge re: mp3 playback on ICs. Is there a handy light-weight MP3 playback chip kicking around? Presumably I'll need to provide memory, an amp and various other bits. Does anyone know of an SoC that does something this already?

I've seen the SOMO-14D (http://www.sparkfun.com/products/9534) but it seems to be very low quality and temperamental. Does anyone have any experience with this? If so, any recommendations?

> Quality is important-ish - I know it's never going to sound like my Technics sound system but I'd like it good enough that a non-audiophile wouldn't complain. I'm guessing I'll need at least 128Kb/s for semi-decent audio.
> Format doesn't have to be MP3 as long as the quality isn't _too_ low and there's an easy way to convert.
> Small size (form factor) would be nice but isn't required.
> If needs be, I can get PCBs etched _relatively_ inexpensively so that's not a major consideration.
> Any suggestions for a good quality, small speaker would also be appreciated.

Skills: I've got a degree in Electrical & Electronic engineering (but haven't touched a circuit since Uni)
Budget: ~£300 tops (I'm hoping for considerably less)
Time: Within a month or so.

Many thanks in advance



Chips exist, but to use them for a new project, without any experience would be pretty nearly impossible. Just buy a cheap player on Ebay, and hack the keyboard.

That is an excellent suggestion, thank you - In fact, that's almost exactly what I was hoping to end up with. Now the only question is do I do it myself for fun or just buy one? :)

Actually, having just had a look, 104 secs @ 16KHz is a little low - I'd planned to pick from a couple of random tracks on activation but it's very handy as a fall-back if I run out of time.

Thanks again

Whilst I may not have any recent experience, I do still know how to hold a soldering iron and working as a software dev. has kelped :) I'm doing this partly to get back into circuits - I recently acquired a netduino and need the refresher. It may take a little longer but I would like to do something more bespoke than emulating a keyboard.

One other advantage is that I can later include this in larger circuits without needing a complete mp3 player.

The other problem is that all these ICs are now surface mounted and fine pitched. See if you can find the AT89C51SND2C for one, although there are some generic chinese parts, with appalling datasheets that you could use.

There's also an ST part, the STA013 - again, if you can still get it - that's worth a try, and isn't too finely pinned, though its SMT.


Yeah, I haven't found much that isn't surface mount in my hunting - at least not worth using. I should be able to do something but I think I'll get my soldering skills up to scratch before I risk short-circuiting pins/cooking the IC :)

Thanks for your advice and help

Don't be too scared, its not actually that hard. Get a cheap propane powered hot air gun.


This may well be the only option but it feels like using a sledgehammer to crack a nut - is there really no better alternative out there? It seems to be about as far from elegant as you can get.

Perhaps I'm just out of touch but we were building circuits which played sound in Uni by oscillating an output bit on the PIC16f84 and passing that through an amp. Needless to say, the sound quality was dire (and mostly square) but I'm amazed that no professionals have done something like this for MP3 on an IC

The great thing about Arduino shields are most of them are open source. So you can get eh schematics for it and make one yourself. Figure out a better design for it and what can tossed out and you can make a basic MP3 player stamp of your own. The group that designed and supports the wave shield kit has some good documentation on it. Check it out!

Here is there design process. If you have any questions about it then contact the people at ladyada and i'm sure they would be happy to help you.

Have you seen this yet? May be just what your looking for. I found it by searching "mp3 player IC" on google.

STA013 ooks like it would do the lions share of what I want - I also have to admit I hadn't considered stripping down the design for one of the arduino shields.

Thanks for some great ideas!

These are nice if you literally only need a musical greeting card. http://www.invitebyvoice.com/push-button-sound-module.html