Class AB, 125W Audio Amplifier
This amplifier is a Class AB design delivering up to 125 W of audio power. It uses a push-pull output stage with complementary transistors: SC5200 (NPN) and SA1940 (PNP) for high-efficiency amplification.
Power Supply
The amplifier requires a symmetrical power supply of +45V and -45V to ensure proper operation of the push-pull output stage.
Key Features
- Class AB topology for high efficiency and low distortion
- Complementary push-pull output using SC5200 and SA1940
- Symmetrical ±45V supply for stable output
- Suitable for driving 8 Ω or 4 Ω speakers with high fidelity
Construction Notes
- Ensure proper heatsinking for both output transistors to prevent thermal runaway.
- Use a well-regulated symmetrical power supply with adequate current rating.
- Keep input and output signal paths separate to minimize oscillation or feedback issues.
- Include decoupling capacitors near the transistors for stability at high frequencies.
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