12W Audio Amplifier based MOSFET 2SK135 / 2SJ50

12W Audio Amplifier based FET Scheme

This is a small 12W audio amplifier over a load of 8 Ω, that combining the NE5534 integrated with a pair of V-MOSFET transistor output stage technology as we get excellent sound performance. MOSFET 2SK135 / 2SJ50 from Hitachi is used in this circuit. Input sensitivity of the circuit is 3V RMS maximum, the distortion factor is 0.002% at 1 kHz, and the frequency response is 15 Hz to 100 kHz. (-3dB).

This circuit requires a symmetrical (dual polarity) power supply with voltage output +/- 25V and the current output should be 2A maximum.

12W Audio Amplifier Components List:

R1 = 33 kΩ C1 = 1nF 63V D1 = 1N967B zener 18V 0.5W
R2 = 6.8 kΩ C2 = 47 µF 40V D2 = 1N967B zener 18V 0.5W
R3 = 22 kΩ C3 = 100 nF 63V D3 = 1N4148
R4 = 100 kΩ C4 = 100 nF 63V D4 = 1N4148
R5 = 1 kΩ C5 = 47 µF 40V Q1 = 2SK135 MOSFET
R6 = 330 Ω C6 = 4.7 pF ceramic Q2 = 2SJ50 MOSFET
R7 = 1 kΩ C7 = 100 µF 40V IC1 = NE5534
R8 = 10 kΩ C8 = 100 µF 40V
R9 = 0.47 Ω 2W
R10 = 0.47 Ω 2W
R11 = 10 kΩ

Power Supply Specification:
Voltage: Symmetrical 25V
Current : 1A – 2A Max

MOSFET 2SK135 and 2SJ50 Datasheet Downloads:


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