This is the circuit diagram of 50W power amplifier based on audio power amplifier IC STK-1050. Symmetrical power supply used to operate this circuit with maximum voltage rated at 53V and recommended supply is 36V. This is a single channel (mono) amplifier circuit, for stereo audio system, you should build two similar circuit. Power supply with minimum 3A center tap transformer should be used for stereo amplifier.
Symmetrical power supply:
- Does not require externally connected emitter resistors.
- Values of emitter resistors have carefully been reviewed to provide superior characteristics.
- Better supply voltage utilization permits designing power supply voltage that are about 0.7V (for RL=4ohms) lower than those required for previous DPP models.
- Maximum allowable power consumption for each resistor is 5W or higher, permitting accomodation for all loads.
- Peak allowable current is 18A or more, providing an ample margin even for peak currents under when short circuited or similar emergencies.
- In particular, maximum output 4 ohms have been enormously improved.
- Use of emitter resistors facilitates meeting different safety standards and designing PCBs
- Mutual interferences in the high-frequency range caused by layout of externally connected emitter resistors no longer exist. This facilitates lower distortion factors.
- Pins are used for emitter resistor output terminals that were not conected in previous DPPs. All other terminals remain uncharged; there is no need for major circuit board changes.
Download STK-1050 datasheet for your project reference: