I need to run a 32 ohm headphone off of 3.3v, but an output voltage of around 3V peak-to-peak has proven to be somewhat inadequate for my needs.

I would like to have a cheap dual-output IC that runs nearly rail-to-rail outputs and is capable of bridge mode. With bridge mode I can get closer to 6V peak-to-peak which has proven to be quite adequate.

It's for an in-headset amplifier, where I have 2 separate wires from each speaker accessible. In fact, I actually need 2 bridged outputs so an ideal part would have quad outputs I can use as 2 bridges.

Actually I got a TEA2025 dual amp which was spec'd as being able to operate off of 3.3v. I soon realized that was somewhat of an exaggeration, its outputs are pretty far from the rail on 3.3v especially at lower frequencies where the speaker has a lower impedance and thus needs to draw more current. It clipped rather easily. I need something closer to a rail-to-rail part.

__________________
I thought what I'd do was I'd pretend I was one of those deaf-mutes.

 

National Semi and TI both have some pretty reasonable selections of speaker amplifier chips. Unfortunately most of the high performance smaller ones tend to be surface mount only (not much need for big DIP sized headphone/small speaker drivers). There's a couple stereo bridged drivers floating around in there, along with a couple 3 legged stereo headphone drivers...

Selection guides:
http://focus.ti.com/paramsearch/docs...ODE_STRY_PGE_T
http://catalog.national.com/Cat/jsp/national.jsp?i=119

 

33mW should be more than enough, are you deaf or something?

__________________
I also post at the following sites:
http://www.stop-microsoft.org http://www.heated-debates.com
Screen name: Aloone_Jonez
And http://www.silicontronics.com, same screen name as here.

 

104mW into 32 ohms, 2.7 to 5.5 volts

http://www.maxim-ic.com/quick_view2.cfm/qv_pk/5237

__________________
If you don't have a planet, what good are gold bars?

want to contact me directly? gmail gordonthree
check out my project website: http://projects.dimension-x.net
Favorite numbers:
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0

 

High noise environment, and also the design of the headset does put the speakers a little further off the ears than usual.

__________________
I thought what I'd do was I'd pretend I was one of those deaf-mutes.