This is a design circuit for audio power amplifier using protection circuit. This circuit is based on LM4951A. This is the figure of the circuit;
The LM4951A is an audio power amplifier designed for applications with supply voltages ranging from 2.7V up to 9V. The LM4951A is capable of delivering 1.8W continuous average power with less than 1% THD+N into a bridge connected 8Ω load when operating from a 7.5VDC power supply. Boomer audio power amplifiers were designed specifically to provide high quality output power with a minimal amount of external components. The LM4951A does not require bootstrap capacitors, or snubber circuits.
The LM4951A features a low-power consumption active-low shutdown mode. Additionally, the LM4951A features an internal thermal shutdown protection mechanism and short circuit protection. The LM4951A contains advanced pop & click circuitry that eliminates noises which would otherwise occur during turn-on and turn-off transitions. The LM4951A is unity-gain stable and can be configured by external gain-setting resistors.
[Circuit schematic source: National Semiconductor Notes]