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tl072

Started by newperson, June 25, 2012, 03:12:49 AM

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newperson

Hi,
What is the smallest circuit that could be build to use as a test circuit for a TL072 IC?

gregwbush

The simplest circuit i have built with a tl072 (dual op amp) uses just one of the op amps and is the AMZ op amp buffer

http://www.muzique.com/news/opamp-buffer-layout/

That'll tell you if it works... (assuming that's what you mean by test circuit... if not, please elaborate!)

newperson

Thanks for the reply.  I think I would need something using both sides of the amp to make sure the ICs fully work.  And yes this is what I am looking for in a 'test circuit.'


LucifersTrip

can't you just hook up the same circuit separately for both sides of the opamp?
always think outside the box

gregwbush

It would be very unlikely that if the chip works, one half of it doesn't, but i understand you want peace of mind  ;)

You could do as LucifersTrip suggests and build a dual buffer

As it happens, i did a vero (strip-board) layout some time ago for one... I'm just labeling components better for you now, and i'll post it....

Ok here it is

jk-fm

Triangle oscillator! 3 resistors, 1 cap, + 2 resistors for vref

gregwbush

you can plug a guitar into mine  ;D

pufferton

Quote from: gregwbush on June 25, 2012, 07:49:21 PM
It would be very unlikely that if the chip works, one half of it doesn't, but i understand you want peace of mind  ;)

You could do as LucifersTrip suggests and build a dual buffer

As it happens, i did a vero (strip-board) layout some time ago for one... I'm just labeling components better for you now, and i'll post it....

Ok here it is


has this build been tested and verified? im trying to build it and running into grounding issues...(continues popping and LED flashes) but not seeing any issues with it...

psychedelicfish

Quote from: pufferton on August 11, 2013, 09:30:28 PM
has this build been tested and verified? im trying to build it and running into grounding issues...(continues popping and LED flashes) but not seeing any issues with it...
The layout looks perfectly fine to me. Are you sure you've wired everything correctly and that there are no solder bridges, badly cut traces etc.? Popping might suggest a backwards electrolytic capacitor, I would recommend checking you have all of them correctly oriented
If at first you don't succeed... use bigger transistors!

pufferton

just triple checked everything...had some issues, fixed them but still the same problem....would it do this if i had a bad component? i removed the board from the chain and i get 9v from the dc jack and LED shines steady. no 1/4" jacks are hooked as of right now.  as soon as i wire everything back up its flashes and i get 1-2v reading.

pufferton

Quote from: psychedelicfish on August 12, 2013, 12:36:01 AM
Quote from: pufferton on August 11, 2013, 09:30:28 PM
has this build been tested and verified? im trying to build it and running into grounding issues...(continues popping and LED flashes) but not seeing any issues with it...
The layout looks perfectly fine to me. Are you sure you've wired everything correctly and that there are no solder bridges, badly cut traces etc.? Popping might suggest a backwards electrolytic capacitor, I would recommend checking you have all of them correctly oriented

http://postimg.org/gallery/alul4cjk/

so it looks extreamly messy cause i have taken it apart 4-5 times.... 

any idea??

davent

Tangentsoft's IC tester. Can be built to test single, dual or quad opamps.

http://tangentsoft.net/elec/opamp-tester.html
"If you always do what you always did- you always get what you always got." - Unknown
https://chrome.google.com/webstore/detail/photobucket-hotlink-fix/kegnjbncdcliihbemealioapbifiaedg

stallik

Hey! A duplicate post... Ic still looks to be upside down
Insanity: doing the same thing over and over again and expecting different results. Albert Einstein

pufferton

Quote from: stallik on August 13, 2013, 06:16:12 PM
Hey! A duplicate post... Ic still looks to be upside down

sorry about the duplicate. i was dealing with two different things and the problems converged. i will try switching it tomorrow. thanks so much for your help!!

stallik

No worries, I thought I was having a de ja vu moment - I've had them before
Insanity: doing the same thing over and over again and expecting different results. Albert Einstein