Circuits

Amplifiers – Biasing (2)

  • Class AB — some collector current flows in quiescent case.  Positive and part of negative cycle amplified;  reaches 50-60% efficiency.  Linearity and lack of harmonic output not as good as Class A but it is acceptable
  • Class B — the transistor is biased on the edge of conduction (600mV for Si), only 180° amplified;  efficiency reached 65% with acceptable linearity and harmonic output