Part I - Background, Characteristics and Fundamental Operations

Last modified by Microchip on 2023/11/09 08:59

Key Concepts

  • The operational amplifier, often referred to as an op-amp, is a very high gain, directly coupled voltage amplifier with two inputs(VIN+, VIN-) and a single output(VOUT).
  • Widely used in electronic applications such as audio, medical devices, and automotive applications.
  • Directly Coupled (DC) voltage amplifier maintains its gain at low frequencies down to dc.
  • Ability to recognize the proper pin orientation of an integrated circuit
  • The differential amplifier as the first stage of an op-amp
  • The differential input mode of operation
  • The common-mode input of operation
  • The differential voltage gain (Av(d))
  • The common-mode gain (Acm)
  • Op-amps amplify any signal that is applied to the inputs.
  • Electrical noise can have a major impact on op-amp operation.
  • The ability of an op-amp to reject common-mode noise signals (CMRR)
  • The rate at which the output of an op-amp can change in response to a change at the input (slew rate)

Op-amps can be configured as amplifiers, comparators, integrators, differentiators, filters, oscillators, and special-purpose amplifiers. If configured as an amplifier, an op-amp can be connected in closed-loop and open-loop configurations using the concepts of both negative and positive feedback.

  • Microchip offers a wide selection of op-amps.

MCP661 op-amp


MCP661 60 MHz, 32 V/μs Rail-to-Rail Output (RRO) Op-Amp in SOIC-8