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LMV341: Can I use this Amp for voltage follower circuit ?

Part Number: LMV341


I want to use this amplifier for the voltage follower circuit.

However, when I simulate the circuit, the gain characteristic seems to be unstable with capacitive load (0.2uF or so).

As a common countermeasure, there is a method of connecting a series resistor to the output terminal (outside the loop) of the amplifier, but is there a disadvantage of this method?

Please tell me how to use this amplifier stably as a voltage follower circuit.

  • User,

    Yes, a outside the loop resistor helps.

    Final output voltage can drop with output current VOUT = VIN - R * IOUT

    Two resistors and a capacitor solution solves that problem.

    Here is a circuit to test. Phase margin = 87 degrees

    LMV431,2 Cap Drive.TSC

  • Hi, Ron
    Thank you for your help.

    But I can not understand part of this circuit.

    - How does L1 (1kH?) Work?
    - What is "B" in the circuit?

  • L1 and C3 create a DC operating point for the op amp. L1 and C3 are large enough thet for any practical frequency the feedback path is open loop. Therefore a AC transfer function at "B" (just a letter I picked) will show the loop bandwidth, gain and phase margins.

    Normal usage after checking stability is complete will be to make L1 and C3 zero (remove them)

    Unground non-inverting input and connect your input voltage.

    It is OK to make supplies single supply.