Introduction to Operational Amplifiers

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Introduction to Operational Amplifiers
Introduction to Operational Amplifiers

• Cyrus Christian R. Almero

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Introduction to Operational Amplifiers

• Operational Amplifier (Op Amp) Diagram

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Introduction to Operational Amplifiers

• Characteristics of Operational Amplifiers
• High input impedance
• Low output impedance
• Internal gain that varies with frequency

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Introduction to Operational Amplifiers

• Characteristics of Operational Amplifiers
• High input impedance
• When the output of a device is used as the input
  to an op amp, the op amp effectivelybecomes the
  load on the input device. In low level voltage
  and current applications that involvetransducers,
  it is important that the op amp draw as little
  current as possible from its input device
  becauseif the current drawn by the op amp
  exceeds that amount of current that the input
  device can supply,then the input device's output
  voltage will fall and not represent the true
  value of the device's output.

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Introduction to Operational Amplifiers

• Characteristics of Operational Amplifiers
• Low output impedance
• Op amps have low output impedances so that their
  output voltages will not be lost
  internally.Another huge advantage to high input
  impedance/low output impedance is that if the
  circuit connected to the outputof the op amp
  requires much current, that current will be drawn
  from the op amp, not the voltage sourceconnected
  to it. The op amp is not an infinite source of
  power, however, because all op amps have
  limitations onthe amount of current they can
  provide. The current must come from the power
  supplies and through the op amp.
• Internal gain that varies with frequency