LM386 with 3.3v

Forum 2005-2010 (read only) Hardware Interfacing
1

Hi, I'm making a PCB to control a Speakjet with an Arduino Fio. I wish to amplify the signal with an LM386, but all the example schematics I see power the op-amp with 5v or 9v. The FIO provides 3.3v (as far as I can tell), but can I use the same schematic, or do I have to change all the resister and capacitor values?

2

Data sheet shows 4 volts minimum required, and 5 volt minimum required, depending on -option of device, so mostly likely won't perform well if at all at 3.3vdc. I'm sure there are more modern chips that would function at 3.3vdc if you search. Perhaps this one:

http://www.national.com/mpf/LM/LM4951.html#Overview

http://www.national.com/ds/LM/LM386.pdf

Lefty

3

Thanks Lefty, I'd not thought to look at Vmin in the datasheet. Looking around, this seems like an ideal one:
http://www.national.com/mpf/LM/LM4915.html#Overview
It is a low voltage audio amp, and requires only V+ and ground, not V+ and V-. What do you think?