30W Class AB power amplifier circuit
diagram using power transistor. Set the above amplifier up by adjust the
variable resistor R1 to maximum and R12 to zero. After this set up is
done, the activate / turn on the amplifier. Adjust the R1 so that the
measured output offset is between 30 and 100mV. Once set, adjust the R12
slowly to achieve a quiescent current of around 120mA. Keep checking
the quiescent current as the amplifier heats up as it might change due
to voltage drop changes in the output devices because of the heat. The
heatsinks should be 0.6K/W or less for two amplifiers.
Power supply circuit for 30W class AB power amplifier:
30W Class AB Power Amplifier Circuit, Link
