Hey there,
I've been trying to interface an electret microphone with a PIC microcontroller for a gift I'd like to give to somebody.
I've tried a few circuits involving NPN transistors, LM358 and LM386 ICs. None of them have seemed to work for me (see below), as the output signals yielded no usable data for me (checked with scope and through a simple ADC-to-serial routine I churned out).
I think the issue is a damaged microphone, caused by incorrect placement into the breadboard (eventually causing the mic to overheat). I am not sure if that is the issue, or just due to the fact that I am testing this on a breadboard.
But since I'm going to be ordering some parts anyways, I'd like to grab the right IC for the job, along with what ever I need to get this thing working. Basically I'm trying to get as nice of a signal as possible to the microcontroller, enough to distinguish peaks in music with the mic placed no farther than 10 cm from source.
I was wondering if anyone had any recommendations. I've seen Audioguru's TL071-based circuits he has posted numerous times on the forums, but my circuit will be powered by 4-AA batteries so something in the 5V Vin range is what I'm after.
Thanks very much!
Links:
First schematic (Top section involving LM386N) **broken link removed**
I was fairly confident on this one until I tried it... very noisy output which doesn't work until I blow very hard into the microphone.
Second schematic I attempted: **broken link removed**
Still nothing.
I've been trying to interface an electret microphone with a PIC microcontroller for a gift I'd like to give to somebody.
I've tried a few circuits involving NPN transistors, LM358 and LM386 ICs. None of them have seemed to work for me (see below), as the output signals yielded no usable data for me (checked with scope and through a simple ADC-to-serial routine I churned out).
I think the issue is a damaged microphone, caused by incorrect placement into the breadboard (eventually causing the mic to overheat). I am not sure if that is the issue, or just due to the fact that I am testing this on a breadboard.
But since I'm going to be ordering some parts anyways, I'd like to grab the right IC for the job, along with what ever I need to get this thing working. Basically I'm trying to get as nice of a signal as possible to the microcontroller, enough to distinguish peaks in music with the mic placed no farther than 10 cm from source.
I was wondering if anyone had any recommendations. I've seen Audioguru's TL071-based circuits he has posted numerous times on the forums, but my circuit will be powered by 4-AA batteries so something in the 5V Vin range is what I'm after.
Thanks very much!
Links:
First schematic (Top section involving LM386N) **broken link removed**
I was fairly confident on this one until I tried it... very noisy output which doesn't work until I blow very hard into the microphone.
Second schematic I attempted: **broken link removed**
Still nothing.