场效应管(MOSFET)组成的25W音频功率放大器电路图

输出功率:25V,8ohm负载.

灵敏度: 200mV 输入 25W 输出

频率响应:30Hz to 20KHz -1dB

THD @ 1KHz: 0.1W 0.014%  1W 0.006%  10W 0.006%  20W 0.007%  25W 0.01%
THD: 0.1W  0.024% 1W 0.016% 10W 0.02%  20W 0.045%  25W 0.07%

音频功放电路:

R1 = 3K3 1/2W 电阻    
C1 = 10nF 1000V 薄膜电容器
C2,C3 = 4700΅F 50V 电解电容器
C4,C5 = 100nF 63V 薄膜电容器   
D1 200V 8A 整流桥,读都也可以用四个整流二极管
D2 发光二极管
F1,F2 3.15A 保险丝   
电源变压器次级输出25V+25V(中间抽头).   
PL1 插座   
SW1 开关

注意事项

Can be directly connected to CD players, tuners and tape recorders. Simply add a 10K Log potentiometer (dual gang for stereo) and a switch to cope with the various sources you need.

Q6 & Q7 must have a small U-shaped heatsink.

Q8 & Q9 must be mounted on heatsink.

Adjust R11 to set quiescent current at 100mA (best measured with an Avo-meter in series with Q8 Drain) with no input signal.

A correct grounding is very important to eliminate hum and ground loops. Connect in the same point the ground sides of R1, R4, R9, C3 to C8. Connect C11 at output ground. Then connect separately the input and output grounds at power supply ground.