Improved Class AB Amplifier

Input impedance - 27K Output impedance - 8ohm Current gain - 3375 Voltage gain - 55 Output power - 22W sinewave RMS Average draw - 52W RMS Quiscent I/P - 367mA / 22W Efficiency - 44% Frequency response - 20Hz - well above 20Khz. Maybe up to 100Khz Close switch for 4ohms Excuse me if there is some miscalculation on my side. I keep changing the circuit and can't keep up correcting the parameters. The second Negative feedback is optional and should be employed with 4ohm loads otherwise a few modifications may be needed to avoid cut off clipping. It will further decrease the THD's but it will somewhat decrease the gain too. It can be easily reconstructed in class B mode. It's all about setting the quiescent current. With a few slight improvements I've increased the efficiency stability and output power a little and the THD levels might be better the low power reproduction is improved by shifting the class B amp slightly in class A mode thus amplifying the low level signals linearly in class A mode while the high power levels are handled by the class B stage You can either use with +/- 25V split rail supply or 50V single rail supply but remember if you use it with single rail you must decouple the output.

published 11 years ago