100W Audio Amplifier Transistor by BDW84-BDW83
The Circuit operates a symmetrical ± 40 VDC power supply and determines the maximum current of 2.6 A. The input circuit of amplifier is a differential amplifier built around Q4 and Q5 that employ DC feedback thus preventing any DC voltage appearing across the speaker with the usual destructive results. Q11 acts as a current source and ensures that the input stage draws a constant current of 1 mA.
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