Very compact class D Audio Amplifier with on-board power supply. the size of the amplifier is 100mm long, 50mm wide and 40mm tall. Output power is 2x70W on 4 Ohms load impedance. The output power can be increased to 2x100W by using other IC such as TDA8950 and a bigger heatsink. The supply voltage is within the range of 90-250V AC, 50 or 60Hz. Signal input can be balanced or unbalanced, and can be chosen from onboard jumpers. Also can be used in BTL mode with balanced or unbalanced input. It has the Mute function and LED visual indication for the amplifier status. The amplifier features over-voltage, over-current and short-circuit protections. The amplifier gain is 30dB in Single-ended mode and 36dB in BTL mode.