I think I may have fried this IC. Is it possible to test it with a DMM?
TLE2071CP Texas Instruments | Mouser Australia
TLE2071CP Texas Instruments | Mouser Australia
When you fry an OP-AMP, very often one of the signal pins has a permanent low impedance connection to Vcc- (negative supply) or Vcc+ (positive supply) terminals. Without supply voltage, you should measure an impedance above 200R from any of the five signal pins to Vcc- and Vcc+. Check also the impedance from Vcc+ to Vcc-.
If this test is successful, you continue the check by setting it up as a voltage follower.
If this test is successful, you continue the check by setting it up as a voltage follower.
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I was wondering that as well
Simple answer is that it is not possible to test with a DVM as only catastrophic failure modes would should doing that.
You need to be pretty determined to zap a device like this. Reversing the supply would be one method and also applying high voltages to the inputs/output while the device is unpowered would be another. Unless you have done any of these then I would give fair odds that the device is OK.
These things are so cheap that its simply not worth wondering over... just replace it. A TL072 would be fine.
Basic functionality can be checked by configuring a simple circuit around it, also measuring supply current is another useful test but beyond that it gets more difficult to confirm the device still meets its specs.
If the chip is in a PCB, used for audio, odds are any DC on the output means it's bad, and/or if it gets hot. If the chip is loose, easiest is to put it in a "Eblock" prototype board and wire up a simple amplifier or oscillator and see if it works. Or since the pin-out is standard, you may have a socket in something that you can drop it into.
Ok, thanks for the replies. Not sure if there's something else I can use instead?
What happened is, in my haste and inexperience building a class D poweramp I installed it wrong. Really wrong. It has 8 legs and 4 of them went into 2 slots of it's mount on the pcb. When I powered up the amp, it blew a fuse and also IC1 which is a IRS2092S. It sparked and now has a hole in it. So I've ordered 3 of those anyway but I haven't found the opamp with cheap postage yet in Australia. Not even sure if it's dead but I'm assuming that it was the cause of the other problems. I built 2 of these poweramps for hopefully stereo operation and the other one works great! I'm hoping it's not completely destroyed anyway and I'm hesitant to put the opamp back in with the new irs2092s when it arrives in case it kills it again.
In case you hadn't noticed I'm somewhat of a novice at amp building. But hey it's been fun...
This is the kit anyway https://www.altronics.com.au/p/k5181-classic-250w-class-d-audio-amplifier-kit/
Edit - Just found a place with free delivery! Ordered 3. That way I can blow up a few more before I find out what else might have gone wrong there...
What happened is, in my haste and inexperience building a class D poweramp I installed it wrong. Really wrong. It has 8 legs and 4 of them went into 2 slots of it's mount on the pcb. When I powered up the amp, it blew a fuse and also IC1 which is a IRS2092S. It sparked and now has a hole in it. So I've ordered 3 of those anyway but I haven't found the opamp with cheap postage yet in Australia. Not even sure if it's dead but I'm assuming that it was the cause of the other problems. I built 2 of these poweramps for hopefully stereo operation and the other one works great! I'm hoping it's not completely destroyed anyway and I'm hesitant to put the opamp back in with the new irs2092s when it arrives in case it kills it again.
In case you hadn't noticed I'm somewhat of a novice at amp building. But hey it's been fun...
This is the kit anyway https://www.altronics.com.au/p/k5181-classic-250w-class-d-audio-amplifier-kit/
Edit - Just found a place with free delivery! Ordered 3. That way I can blow up a few more before I find out what else might have gone wrong there...
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it all works with the new one. 
If the 2092 blew up its possible you fried the output mosfets too as its possible they were both switched on at same time. So check mosfets for shorts between all pins. They usually go short s-d but I have seen a short between g-s.
Change the 2092 anyway as mosfets blowing usually take out the 2092 as well.
Check the mosfet gate resistors for open circuit too.
I have blown a few 2092's so an expert on them !!
It's not such a safe thing to probe an unpowered op amp with a multimeter in resistance mode. The multimeter test current can reverse bias random things inside of the op amp, and mess them up when they were not messed up before. Besides, what are you going to compare these readings to? The IC is not intended to be used this way, so you're in uncharted ground.
A far better idea is to simply power it up in a basic circuit like a follower or inverter and see what it does. When it's powered, you can read the voltage between the + and - inputs, and if the feedback loop is closed, the voltage should be nearly identical. If not, the amp is dead. The output voltage should also be within the power supply rails, assuming the circuit is running the amp in its linear region. If not, the amp is dead. And so on. But, stuffing random currents into an unpowered IC with a meter can cause a chip to fail, and it doesn't really tell you much that's interesting either.
A far better idea is to simply power it up in a basic circuit like a follower or inverter and see what it does. When it's powered, you can read the voltage between the + and - inputs, and if the feedback loop is closed, the voltage should be nearly identical. If not, the amp is dead. The output voltage should also be within the power supply rails, assuming the circuit is running the amp in its linear region. If not, the amp is dead. And so on. But, stuffing random currents into an unpowered IC with a meter can cause a chip to fail, and it doesn't really tell you much that's interesting either.
I wouldn't have thought a multimeter would put out enough volts/current to blow an op amp.
They are used for testing diodes and transistors so it should be ok.
I suspect the op amp (out of circuit) is more prone to ESD from touching it.
I guess my point is more that it's hard to make sense of probing an IC, since you might run into clamp diodes or parasitic junctions - I'm not sure what I'd assume when getting a reading. A simple diode or transistor is more predictable, and yes, they can be probed meaningfully. It's possibly safe, but hard to make sense of the results, and possibly dangerous. A simple test for something more complex than a single junction is just to power the circuit up and see if it works.
The initial question was: "Is it possible to test it with a DMM?".
The test I am aware of, using a DMM only, is the impedance test. Like Nigel, I doubt that an Ohm-meter put in the 20K range can damage an OP-AMP rated for operation at up to 38V. This is not a low voltage IC. At least, I have used this method for long.
It is evidently only a negative fatality test. If the IC fails, it is very likely to be defect. If the IC passes, it is not certain it is in good shape. Then, tests "in vivo" will be necessary. But, tests if the IC still performs to specs are cumbersome and in case of doubt, replace it.
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38V is a typical maximum power supply spec, but we're talking about probing an un-powered IC. I just looked up the ancient LM318 and it spec's no more than a volt or so between the input terminals. There are a lot of voltage specs on a complex IC.
Regardless, and I repeat... what are you going to do with a "resistance measurement" with some random meter's test current between two terminals of a random IC, one whose innards you know nothing about? I just don't see the point, even if it is safe. Maybe it feels good to place hands upon a dead or not dead chip and make a pronouncement, but wouldn't it be more fruitful to just test the thing powered up or toss it?
Regardless, and I repeat... what are you going to do with a "resistance measurement" with some random meter's test current between two terminals of a random IC, one whose innards you know nothing about? I just don't see the point, even if it is safe. Maybe it feels good to place hands upon a dead or not dead chip and make a pronouncement, but wouldn't it be more fruitful to just test the thing powered up or toss it?
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