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Problems with LM1036 amplifier

Okay, so we're doing an electronics project in school. Bear in mind that I'm not that experienced in this field. Anyway, we've built an amplifier circuit which contains, among other things, an LM1036 amplifier. We're having some problems with this component.

On page 7 of the datasheet found here http://www.ti.com/lit/ds/symlink/lm1036.pdf you can see how this component is applied. We've used pretty much the exact component for resistors, caps and such.

Now here's the problem. If we send a sine wave to input 1, we get a corresponding sine wave on output 1 but with increased amplitude. Pretty much what we want. However if we send a sine wave to input two, we somehow get a DC voltage at output two. The DC voltage we get is the same as the supply voltage we're using, so it might be related to that somehow. However, we don't know why we get this, and as you understand it is quite troublesome, as we need to use both inputs.

Any ideas of how we might have screwed up this circuit?
 
I recheck my circuit wiring again. Carefully. Don't just assume something is wired correctly, eyeball it.
If your circuit is correct, you may have blown your IC.
 
Yeah, we've checked this several times already. Probably gonna check for any bad soldering tomorrow. Otherwise we'll try with another IC I guess.
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Very carefully check everything connected to pin 13 and 19. Is pin 13 bridged to pin 12, for example?
 

KrisBlueNZ

Sadly passed away in 2015
Also, compare the voltages on the external capacitor pins between the two channels. A problem on those pins will mess up the DC conditions on the channel.

Compare voltages on the following pairs of pins:

pin 3 and pin 18
pin 5 and pin 16
pin 6 and pin 15

If there's any significant difference, check the connections to the pin on the pin 11 to pin 20 side of the IC.
 
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