The circuit shown in the figure is suggested by ON Semiconductor (www.onsemi.com), based on its NCP4896 integrated circuit. It is an amplifier that can provide 1 W of power in BTL configuration with a load of 8 ohms from a 5 V supply. This circuit also supplies 250 mW with a 2.6 V supply and 90 mW with a 32 ohms load. and 5 V power. The device provides high audio quality while requiring few external components. We also found the shutdown feature for low consumption from external logic. The supply voltage range is from 2.2 V to 5.5 V and the enclosure of the integrated circuit is 9-pin Flip-Chip. The device can also excite capacitive loads up to 1 nF and I have it externally configurable. As the circuit has excellent PSRR, it can be powered directly by a battery without the need to insert an LDO.
