Microphone advice...

kam · Joined: 15 Jul 2005 Posts: 59

Hi all,

Well, another project...

I want to use a microphone and capture sound. Then ultimatly play the sound back. I know there are IC's that do that, but I will be passing the sound via ??? (serial, usb, bluetooth etc) to the player side.

I can pass the data thats not the problem.

Being a novice at eletronics, my questions are:

#1. I want to capture sound, use the A/D to give me data
#2. Take the data, and play the sound

Can anyone give advice on what hardware I need? I'm not interested in CD quality sound, just simple mono phone quility.

The pic will be the pic18f4520@40mhz on both ends

[novice electronics person now speaking]
It seems that capturing the sound should be easy, a condenser mic hooked to lets say A0 on the pic (I'm not sure what caps/res/etc I need)

The playback, thats where I'm lost since I'm sure I need an amp type of thang to play on a speaker...
[end of novice electronics person now speaking]

Any advice would be greatly appriciated!

~Kam (^8*

gbolson · Joined: 24 Oct 2006 Posts: 7

kam,
Microchip has an app note on this (AN643). You can download the app and the source code here.
As a word of warning... it was written for a different compiler, so there are a few changes that will need to be made, but it's a good starting point.
Greg

kam · Joined: 15 Jul 2005 Posts: 59

Thanks Greg, I'm not worried about the code, just the electronics...I just need to know how/what to wire!

~Kam (^8*

gbolson · Joined: 24 Oct 2006 Posts: 7

Kam,
The app note includes a schematic in Appendix E
Greg

KamPutty · Guest

Hi Greg,

I've been looking at the schematic for about 45 minutes. Every 5 minutes, I turn the page 90 degrees to the right to see if it makes more sense Sad

I can locate the speaker amp, but where is the microphone? Is it the "4th Order Butterworth LPF @ 4kHz?"

I tell you, not knowing much about electronics can be a real pain in the butt. I've got to believe that someone must have a IC that does the capture, and pre-amp stuff...you know, read the microphone NOW and give me the data, then here's the data, push it to the speaker...simple and sweet. I just need to quickly prototype a few things and this is stopping me in my tracks! ah! Shocked

Again, thanks for the doc (I'll need another type of doc after my head explodes!)

~Kam (^8*

PCM programmer · Joined: 06 Sep 2003 Posts: 21708

There is no audio input. Look at the block diagram (Figure 3) on page 6.

To search for microphone articles at the Microchip website, you can use
this search string with Google:

Guest · Posted: Tue Oct 24, 2006 2:48 pm