DPRG List  

[DPRG] Driving a speaker

Subject: [DPRG] Driving a speaker
From: Dan Miner miner at centtech.com
Date: Sun Jan 25 11:43:01 CST 2004

Thanks Bob.  (And Ralph and Dale who emailed me privately.)
It looks like the LM386 is exactly what I'm looking for.

Thanks guys.

				- Dan

> From: Robert Jordan 
> Sent: Saturday, January 24, 2004 5:42 PM
> Dan,,
> A class B amplifier isolated with a cap
> or a tuned circuit for better matching
> would work. Class B is two complimentary
> transistor driving each side of the
> signal. The cap makes the DC signal
> AC to drive the circuit. Cheap and EZ!
> OR try an amp chip like this on
> LM386 IC power amp for Radio Shack.
> http://www.minidisc.org/schem.gif
> Use 8 ohm speaker if your amp (transistor
> or IC) matches that impedance.
> If you drive a speaker from a MCU, use
> a cap and a high ohm speaker like 100 ohm
> 32 ohm with a resistor, to not load
> the I/O pin and avoid distortion.
> bob
> -----Original Message-----
> From: dprglist-admin at dprg.org 
> Sent: Saturday, January 24, 2004 12:27 PM
> I'm putting a speaker on a current project.  My first thought
> was to drive the speaker with the output pin but I quickly 
> realized that there wouldn't be enough current.  So, just
> add an NPN or N-channel FET, right?  But that's not great
> either because it only allows a half-wave square wave at 
> best.
> Now I'm thinking I need an H-bridge to drive the speaker.
> Can anyone give me a better suggestion or tell me where
> I'm going wrong?
> 				- Dan Miner

More information about the DPRG mailing list