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op484 is getting heated

I am using OP484 as an inverting amplifier .

But as soon as i powered up my board all OP484 start heating to very high temperature..

i have attached my schematic .

Please tell what is wrong in that.

There are no floating pin i have connected sensor output to all inverting inputs.

  • output of any op amp is 0 volt.

    I checked with multi meter and by oscilloscope both.

    okay i will change it but i need 1/3 gain  of the inverting amplifier . I will ensure the ratio by changing both the resistor value.

    input and feedback(R1 and RF).


    okay ,Yes i will use ADA4084.

    It is to get final positive output .

    Inverting  cascaded to unity gain inverting amplifier. Is it not correct method to do so?

  • Thanks harry .

    understood .

    Here i learnt theory can not be directly applied to get a  working board.

    I will update the board.

    Is there is any other problem in the circuit??

  • FormerMember
    0 FormerMember
on May 29, 2017 10:16 PM

--  You have no voltage readings??

--  Lots of Rfeedback resistors are 1k, too low.   Double it to 2k and 3k to 6k.

--  Use next generation ADA4084-4;  lower supply current.

--  Several op amps, such as U14B  U14D have outputs shorted together.  What do you want to do?


  • If you want to invert the output of the first op amp, then for the second op amp, you have to ground

    the non-inverting input and have a 5k input resistor and a 5k feedback resistor.  Sorry, you have

    to spin your board.

    Also, for precision signal chains, I would use two duals (ADA4084-2) instead of a quad:

    Planet Analog - Harry Holt - Op amps: to dual or not to dual? (Part 1 of 2) 

    Planet Analog - Harry Holt - Op amps: to dual or not to dual? (Part 2 of 2) 


  • Nothing obvious.

      Also read MT-032 to MT-060 at


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