Transimpedance (Gm) Amplifier

The circuit below shows a transimpedance (Gm) amplifier as formed by an MCP6XXX Op Amp and R1. It converts the sensor current (ISEN) to a voltage. The capacitor C1 is sometimes needed to stabilize the amplifier when the source has a large capacitance.

gm-amp.png

Advantages:

  • Good impedance buffering of source
  • Simplicity

Disadvantages:

  • Design may need to be stabilized

Sensor Examples:

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