Forums

LM386 oscillator challenge

Started by bitrex October 26, 2015
So here's a schematic of a standard LM386 power oscillator:

http://www.interfacebus.com/lm386-square-wave-oscillator-circuit.jpg

I have an idea for a thing where what I'd like to have is a second LM386
oscillating at the same frequency and amplitude, but opposite phase as 
the first one, for push-pull drive. But I'd like to not use any further 
active parts other than the second LM386, if that's possible.

I know there are other chips that could probably do what I want more 
easily, but this is just for a little breadboard experiment and I happen 
to have a bunch of these sitting around.
LM386 just went on lifetime buy...

Steve 
On Mon, 26 Oct 2015 14:30:06 -0400, bitrex wrote:

> So here's a schematic of a standard LM386 power oscillator: > > http://www.interfacebus.com/lm386-square-wave-oscillator-circuit.jpg > > I have an idea for a thing where what I'd like to have is a second LM386 > oscillating at the same frequency and amplitude, but opposite phase as > the first one, for push-pull drive. But I'd like to not use any further > active parts other than the second LM386, if that's possible. > > I know there are other chips that could probably do what I want more > easily, but this is just for a little breadboard experiment and I happen > to have a bunch of these sitting around.
Rig up one as the oscillator, the other as an amplifier with a gain of -1. -- www.wescottdesign.com
On Mon, 26 Oct 2015 11:51:10 -0700, sroberts6328 wrote:

> LM386 just went on lifetime buy... > > Steve
TI sez its status is "active". That doesn't sound like "lifetime buy" to me. Unless I'm missing something. -- www.wescottdesign.com

"Tim Wescott" <tim@seemywebsite.com> wrote in message 
news:sf2dnZ6EtJZGHrPLnZ2dnUU7-SMAAAAA@giganews.com...
> On Mon, 26 Oct 2015 11:51:10 -0700, sroberts6328 wrote: > >> LM386 just went on lifetime buy... >> >> Steve > > TI sez its status is "active". That doesn't sound like "lifetime buy" to > me. Unless I'm missing something.
Even if it were a problem - there are other similar chips that could do the job.

"bitrex" <bitrex@de.lete.earthlink.net> wrote in message 
news:OiuXx.431$_%7.188@fx23.iad...
> So here's a schematic of a standard LM386 power oscillator: > > http://www.interfacebus.com/lm386-square-wave-oscillator-circuit.jpg > > I have an idea for a thing where what I'd like to have is a second LM386 > oscillating at the same frequency and amplitude, but opposite phase as the > first one, for push-pull drive. But I'd like to not use any further active > parts other than the second LM386, if that's possible. > > I know there are other chips that could probably do what I want more > easily, but this is just for a little breadboard experiment and I happen > to have a bunch of these sitting around.
A search through various application notes will show various ways of hooking up a pair of AF PA chips in BTL mode. Study some of those and it may become apparent how to combine your oscillator with the 180 deg phase shift used in a BTL. A good circuit to look at is in the application examples for the TDA2822. Some of the NS appnotes are fairly revealing too.
On Monday, October 26, 2015 at 3:49:52 PM UTC-4, Tim Wescott wrote:
> On Mon, 26 Oct 2015 11:51:10 -0700, sroberts6328 wrote: > > > LM386 just went on lifetime buy... > > > > Steve > > TI sez its status is "active". That doesn't sound like "lifetime buy" to > me. Unless I'm missing something. > > -- > www.wescottdesign.com
Digikey says it's EOL (last buy in 2016).. who ya gonna believe? George H.
Den mandag den 26. oktober 2015 kl. 21.03.29 UTC+1 skrev George Herold:
> On Monday, October 26, 2015 at 3:49:52 PM UTC-4, Tim Wescott wrote: > > On Mon, 26 Oct 2015 11:51:10 -0700, sroberts6328 wrote: > > > > > LM386 just went on lifetime buy... > > > > > > Steve > > > > TI sez its status is "active". That doesn't sound like "lifetime buy" to > > me. Unless I'm missing something. > > > > -- > > www.wescottdesign.com > > Digikey says it's EOL (last buy in 2016).. who ya gonna believe? >
afaict it is only the 1W dil version -Lasse
On Monday, October 26, 2015 at 3:49:52 PM UTC-4, Tim Wescott wrote:
> On Mon, 26 Oct 2015 11:51:10 -0700, sroberts6328 wrote: > > > LM386 just went on lifetime buy... > > > > Steve > > TI sez its status is "active". That doesn't sound like "lifetime buy" to > me. Unless I'm missing something. > > -- > www.wescottdesign.com
Tim, See "The Chippocolypse is coming!" on EEV Blog Link: http://www.eevblog.com/forum/projects/the-chippocolypse-is-coming!/ Steve
Tim, 
see http://www.proaudiodesignforum.com/images/pdf/ti_20150901004_09292015_eol.pdf

Steve