I made a post awhile ago about using a 386 audio amplifier chip and an arduino. I got a lot of help and I have it all set up now but I'm having some weird problems.
I'm using this schematic: http://www.hobby-hour.com/electronics/lm386-20.gif
(However, I don't have the exact capacitors...instead of a .05uf, I have a .1uf...instead of a 250uf, I have a 220uf of a 330uf.)
Just in case, here is how I have it set up: Pin 1: nothing, Pin 2: Ground, Pin 3: Using a 10k pot - middle goes to pin 3, one side goes into pin 7 in Arduino, other side goes to ground.
Pin 4: ground, Pin 5: 104 cap in two spaces after pin, followed by a 10ohm resistor with the other end in ground, followed by a 220 or 330uf cap which has it's negative side attached to the + end of speaker. Other end of speaker is grounded. Pin 6 goes to the power rail in breadboard. Pin 7&8: Nothing.
I'm trying to power everything from one source...so I'm powering the Arduino through the Vin pin.
I have everything set up in what seems to be the right pins but when I put the power in the rails of the breadboard with a 9v adapter (This one, clipped and breadboard ready: http://www.adafruit.com/index.php?main_page=product_info&cPath=18&products_id=63
), the sound is very muffled in the speaker and the chip starts to overheat very quickly and one of my 10ohm resistors turned brown even...
If I power everything with a 9v battery, the sound works fine but the chip starts to overheat after a few resets of the arduino. (I'm just running the SimpleMelody example in the digital examples section in the Arduino IDE).
Any ideas? Is it because my caps are the wrong size? Does anyone have experience using a 386 with Arduino?
Thanks for any help!