This audio power amplifier project is based on LM1875 amplifier module from National Semiconductor. It can deliver up to 30W of power using an 8 ohm load & dual 30V DC power supplies. It is designed to operate with maximum outside parts with current limit & thermal shutdown protection features . Other features include high gain, quick slew rate, wide power supply range, giant output voltage swing & high current capability. Summary of the audio amply-fire features: Low distortion: 0.015%, 1 kHz, 20 W Wide power bandwidth: 70 kHz Wide supply range 16V-60V Up to 30 watts output power Internal output protection diodes Protection for AC & DC short circuits to ground 94 dB ripple rejection Plastic power package TO-220 25V Power Supply The schematic below shows how the +25V DC & -25V DC are obtained. In order to provide power supply for two stereo amplifiers, a power transformer rating of 80VA with 240V/36V middle tapped secondary winding is used. The secondary output of ...