SparkFun Forums

[sy1201]

Hey guys

I've recently purchased this part from sparkfun hoping to use it to amplify PWM output from arduino to simple a speaker.

http://www.sparkfun.com/commerce/produc ... ts_id=8704

From what I've read, you use this to amplify the different between the input voltage and the supplied voltage (5V in this case).

Right now I just have the POWER and GND from the breakout board hooked onto power/gnd of arduino, IN hooked onto arduino's PWM, and OUT hooked onto the speaker (other end is grounded).

I still get audio output from the speakers, but not getting any gain in volume. I'm pretty sure I'm not using the chip right, or I'm missing another part completely to use it correctly. Can someone give some pointers?

I'm pretty new to audio and opamp related stuff, so any help is appreciated.

Thanks

[leon_heller]

An ordinary op amp isn't suitable for that application, it won't drive a speaker. I'd use a MOSFET.

Leon

[theatrus]

Many op-amps aren't capable of driving sizable speakers.

Op-amps also depend on feedback to give gain. I'm unsure of your description whether you've wired it for unity gain or something else.

http://en.wikipedia.org/wiki/Operationa ... igurations

[riden]

You want something like a LM386. They are readily available and require few additional components. If you want something complete and ready to go, try this LM386 Audio amplifier mini-board.