Post Go back to editing

About ADA4522-2 scope of input signal voltage

I have an application where the input signal is usually +5V, -5v.

But sometimes it goes up to +8V or -8V.     (VIN scope is 2-22v ;  VF2 scope is -8,+8v)

I don't need more than 5Vso I set the supply voltage to +5v and -5V.

Can this circuit run steadily for a long time?

Thank you!

Parents Reply Children
  • Hi seekyong,

    When your input (VIN) and by extension device inputs (VF2) exceeds the supplies (+/-5V), you are operating the device beyond its Common Mode voltage rating. With no resistance to limit the current into the non-inverting input, you could damage the device by exceeding its Absolute Maximum Rating of +/-10mA input current.

    I think if you add a resistor (1kohm) in series with your non-inverting input, as shown below, to limit the flow of current, you'd be Ok then. Simulation shows that this way you won't exceed the 10mA rating:

    LTspice Simulation file:

    ADA4522 EZ 5_4_20.zip

    Regards,

    Hooman