An amplifier circuit with a widened, even a pre-header ends wilson current mirror circuit boosting - - -

摘要

An amplifier circuit (1) includes an amplifying transistor (QO) and a do bias circuit (2) for biasing the amplifier transistor (QO) to obtain a conduction angle of at least about 180°. The do bias circuit (2) includes a self-bias boosting circuit which has a Wilson current-mirror (Q4, Q5, Q6) integrated with a cascode current-mirror circuit (Q2, Q3) to form an extended Wilson current-mirror circuit (Q2-Q6) having an output coupled to a control terminal of the amplifying transistor (QO) by a resistor (Rl), and a capacitor (C2) coupled from the extended Wilson current-mirror circuit (Q2-Q6) to a common terminal (Gnd).