TL082 dual supply problems

Alex Pummer

Joined Sep 20, 2015
1
I am using some TL082's for a project. I have them connected to a dual supply of which is ±12 (sourced from a 24V 3A supply)

If I look up their datasheet, and I click on this one (The TL082xx) it says:
View attachment 188372 It clearly says the absolute maximum is ±18. 12v is heaps under that maximum.
However, when I connect the +supply of my rail splitter to +Vcc and my -supply to -Vcc, the chip heats up very quickly and gets very hot.
I did some digging and come across something that said along the lines of ±xx is the range. For this, that would mean the max is ±9 which is a total range of 18. This doesn't really line up with the datasheet however, when I give it ±6 (half of 12v), it doesn't heat up. So maybe it is a range.

This is were I left off for a bit. I came back still as confused and decided to google the whole part number (TL082-CP). This has been a mistake I have made before. I found no datasheet because the '-CP' is included the datasheet above. I did loom at the specification in the mouser page though and this is what I found:
View attachment 188375
It definitely says ±12 on there.

Why is my chip heating up so much when powered with ±12? There is no other circuitry with the chip - just on its own. It might be that the chip was faulty but I'm hesitant to use my other one because if it is a fault with my circuit then I will damage the other chip and I will have none left.

Thanks,
Bod.
just take a fast scope -- min 100MHz -- with alow input cap. probe and look the output pin of the amplifier, it may oscillate at very high frequency.
 

eetech00

Joined Jun 8, 2013
1,992
Hi

Make sure your dual power supply shorting link is connected correctly.
Also make sure the one of the opamp inputs has a reference to ground.

If the shorting link is missing or there is a high resistance (or no connection) at opamp to ground, the opamp supply will be at 24v.

eT

1572114447239.png
 
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