Non-obsolete DIP Alternative to LM386?
Bill Chennault
Posts: 1,198
All--
I have done a bit of research and have not found a modern alternative to the LM386 in a DIP package. I could well be missing it in my ignorance.
My needs are for a simple, higher quality audio amplifer (I can barely use these terms). A lower parts count would be great. A single supply (rather than a split supply) would be nice. Does such a part exist?
Thanks!
[Research: A jillion posts on this forum and Google.]
[EDIT: op-amp changed to audio amplifier. I SAID I could barely use these terms!
--Bill
I have done a bit of research and have not found a modern alternative to the LM386 in a DIP package. I could well be missing it in my ignorance.
My needs are for a simple, higher quality audio amplifer (I can barely use these terms). A lower parts count would be great. A single supply (rather than a split supply) would be nice. Does such a part exist?
Thanks!
[Research: A jillion posts on this forum and Google.]
[EDIT: op-amp changed to audio amplifier. I SAID I could barely use these terms!
--Bill
Comments
Try the TDA7052A. Quality is much better and it uses fewer parts.
I will edit my post and fix the glaring error. Thanks!
I had read that the 7052 was no longer produced. Did I get that wrong, too?
--Bill
-Phil
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=LM386N-4-ND
And here's a Digikey link for the TDA7052A DIP:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=568-1138-5-ND
DJ
If memory serves me right, I've used a TL070 JFET opamp in place of the LM386 - I'll have to dig out my notebook when I get home. Also, it may be obsolete too. It's a low noise version of the TL080 opamp. I think Radioshack still carries the TL082 dual version.
Paul
"High quality" = audiophile?
How is the LM386 failing?
The TDA2002 isn't a no-parts "low parts count" panacea, but it cranks.
Could you use that Radio Shack 'mini-amplifier - speaker' (277-1008C)?
[The LM386-4 is 1W, the more common -3 is 700mW.]
The LM386 circuit has some noise in it. My wife mentioned it. (So it must be so.) There is a whine that I can just hear and a tiny bit of static. (Is either indicative of something notable?) It is not actually failing. Since I had some laying around and knew nothing about them, that is what I used. However, before I wrap this project in an enclosure, I am going to experiment with something else. The 7402 seems easy to use. Well, the split power supply has me a little confused, but it must not be terribly complex. I should be able to figure it out once I really look at it. (I would really like to build some battery operated sensor things using the Parallax WiFi module that I can just toss around the house and property and automatically collect data on a server.)
Audiophile quality is not necessary. Just a nice, noise free, circuit for voice only. No huge amplification. (In the vernacular of the biz, does "amplification" = "gain"?) Is that achievable in a low power (6 to 9v) situation?
Since I've discovered the possibilities of this audio stuff for the type of use related to in this thread, my eyes have been opened to a bunch of other applications like toys for my brand new grandchild, voice for my robot efforts, and voice for a BUNCH of little applications on which I want to work. I need to find an appropriate audio amplifier and circuit that hopefully is applicable across a fairly broad range of voice only applications.
I have three projects in the works right now. All three are up and running: An SX48 driven AP-16+ (almost unlimited possibilities; battery power probably not applicable); an APR 9600 device which records and plays 8 selections; and today's effort which is a dual APR 9600 machine which records and plays 16 selections.
The last one mentioned above is going to be the first one I stick in an enclosure. But, it is also the one with which I am experiencing amplification problems . . . the APR 9600s drive the single 8 ohm speaker as loud as the shared LM386 do by themselves. I have "narrowed" the problem down to the dual APR 9600 implementation which I dreamed up.
While all this is going on I am trying to learn CadSoft so I can post some schematics! I hoped CadSoft would let me create a schematic via simple component drag and drop. So far, I haven't figured it out. I need to look into more of those dozens of libraries for one that has resistors and capacitors and chips and stuff. (???)
Thank you for the TDA2002 and Radio Shack 277-1008C ideas. I'll check'em out.
I don't know if I have the LM386-4 or the -3 part. I'll have to look in the morning.
Thank you for thinking about this for me.
--Bill
PS There is a picture of my dual APR 9600 Talking Thing attached. It works just fine, but more amplification would be nice. Realistically, I wonder how big an enclosure will be reguired to enclose one of MY wire wrapped circuits?
Or is it "hummmmmmmmm"? You're working with relatively low level analog signals and then amplifying them - with no shielding around the circuit. You could be picking up 60/120Hz from surrounding electrical equipment/appliances/wiring. Wrap the proto-board in plastic food wrap, then wrap that up in aluminum foil and connect the foil to the proto-board ground. Open a hold through the plastic and foil for the speaker (and with the unit turned on), and see if you hear the hum.
Static? Try disconnecting the output of the 9600 and tie the input of the power amp to ground via a capacitor (1uF would work). Does the static level change? More/less/notatall? Have another power amp to try? Are the 9600 and power amp supply pins bypassed with some caps?
DJ
I've got TDA7052s in the mail from Mouser. Thanks for giving me a clue!
Paul, glad you liked it! The REAL reason it looks good is because I have little electronics experience. (Actually, I have had quite a bit, but it was all over 40 years ago and I have FORGOTTEN most of it.) By laying it out in an orderly fashion, I can easily spend countless hours debugging.
DJ, it is definitely a whine, not a hum. My -speaker wire is long, as is the +input lead. The +input lead has two 0.1uf caps in it. I will try your static test tomorrow. I have plenty of LM386s and have already swapped that component, as well as all the others.
The breadboard I used was on one of my robots. I SMOKED it when I dumbed off with 2400 amp hours of battery power. But, I "fixed" it and stuck it in a drawer only to be pulled out for this project. Since all the components work fine on a different breadboard, I am thinking the breadboard is the culprit. Everything else works well, I just get no more volume than if I let the APR 9600s drive the speaker with no amplifier.
--Bill