TL084 Inputs and Failed Devices

Bill,

A series 10k will be more effective.

If this was the problem then there would likely be a short (or leakage) from input (pin 5) to ground (or maybe VCC).

Hello, i have the same problem, and as well, the component is not working as a comparator at 10KHz, i have a TL084 from 2015 and TI too, that works perfectly even for signal conditioning, so i guess you are right about poor design from TI, i have not found yet a replacement, this is sad, i thought TI was good, all TL084 from ST that i have work perfectly.
i tried to fix this, even in instrumental amplifier, but nothing seems to fix this. the component is poor designed or bad made.

Comparator output rise and fall time will be limited by slew rate. Inputs must be 4V greater than VCC- and less than VCC+ for a valid output low or high.

Inputs are in the required levels, as i say, old TL084 from Texas Instruments work perfectly, this new pieces that i bought are not working, not even for a single voltage follower, my guess is that it was a bad manufacturing. I ordered the NTE replacement to see if it will work.

Thanks for answering

I'm glad to help. If I understand correctly, multiple samples have some or all channels that are not performing in an application that did work with other competitor samples. Can you provide the full part number and distributer used for purchase? If you prefer to do this privately, send me a friend request. How?; click on my name. then choose "connect" (upper right button), then click "request friendship".

the part number is 13WHY28M TL084CN, i have at least 30 of these, and no one work... not even the TL074 from any brand, i tried multiple settings, as adder, as voltage follower, and they just fail, the TL084 from ST works perfectly, and the old one from TI, the problem is that i already delivered the product with the component, so no idea the whole part number of that specific one. And i cannot find any ST TL084, all TL084 that i have found are from Texas Instrument.

Hello Bill, do you have the 13WHY28M TL084CN too?? because they don't work either for me, using a PH probe, with bnc connector, exactly as you.

The first two digits in the name is year and month code; therefore this lot of devices was made in March 2001. These devices are six years old.

Nevertheless it is very odd that none work. Have you tried ordering new samples?

i bought more from ST but the supplier sent more Texas instruments, those were the same code, how can i get samples of a different code? i got 32 useless opamps, and the price and all that is not the problem, the problem is TIME, and having our customers waiting... not good for our enterprise.

Please identify the parts supplier. It is totally unacceptable for the supplier to make this substitution.
Also helpful will be the supplier part number ordered.

For Mexico, try Digikey as a parts supplier (as one example of many recommended supplier)

http://www.digikey.com.mx/en