LM324: LM324 giving floating output when no inputs at the probe

Nagaraju AnilRaju

Part Number: LM324

we are using this OPAMP for Sensing applications, please find below circuit, the Op-Amp giving continuously giving floating values when no probe is inserted, not sure why this happening, can you please check and suggest.

over 7 years ago

0 Ron Michallick over 7 years ago

TI__Guru*** 140146 points

Nagaraju,

What is the supply voltage at pins 4 and 11?

The input voltage should be 2V less than VCC for all temperatures and 1.5V less than VCC at room temperature, 25C.

0 Nagaraju AnilRaju over 7 years ago in reply to Ron Michallick

Prodigy 60 points

Hi Ronald

Thank you so much for your response, Iam applying 5V to the pin:4 and Pin:11 is grounded, in the datasheet not says less than 2V in all temprature

0 Ron Michallick over 7 years ago in reply to Nagaraju AnilRaju

TI__Guru*** 140146 points

Nagaraju,

Are you still having trouble with this issue?
By floating, do you mean the output voltage changes over time? What is the range if this output voltage?
The output should be a stable 3.3V at room temperature.

Amplifiers

Amplifiers forum

LM324: LM324 giving floating output when no inputs at the probe