OPA365: Over voltage supply reliability risk

Part Number: OPA365
Other Parts Discussed in Thread: LM7705

Hi TI expert

What is the risk (damage or relability only ) when the amp. is biased with +5V connected to V+,  and V- is connected to
 500 OHM resistor which the other end of the resistor  is connected to -4V?

Please see schematic capture.

  • Hi Li,

    the OPA365 only withstands a maximum supply voltage of 5.5V. Now it sees 9V and is in danger to be destroyed.

    Why are you doing this? Scream

    Kai

  • Hi Li,

    Kai is absolutely correct. From the datasheet section 7.1 Absolute Maximum Ratings, "Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability"

    This circuit far exceeds the device limitations and I would advise against it.

    A simple fix would be to connect the negative supply pin to ground, as the device is well suited to single supply operation.

  • If your input needs to go to ground, consider the LM7705 on the negative supply to get enough output headroom for correct operation