LM4663

LM4663 2 Watt Stereo Class D Audio Power Amplifier with Stereo Headphone Amplifier January 2000 LM4663 2 Watt Stereo Class D Audio Power Amplifier with Stereo Headphone Amplifier General Description The LM4663 is a fully integrated single supply, high efficiency Class D audio power amplifier solution. The LM4663 utilizes a continuous time delta-sigma modulation technique that lowers output noise and THD when compared to conventional pulse width modulators. The LM4663 also features a stereo headphone amplifier that delivers 80mW into a 32Ω headset with less than 0.5% THD. The LM4663 has two stereo inputs that can be selected to drive either the headphone amplifier or the Class D amplifier. All amplifiers are protected with thermal shutdown. In standby mode, the LM4663 draws an extremely low 2µA supply current. With a 4Ω load, the IC’s efficiency for a 250mW power level is 69%, reaching 83% at a power level of 2W. The IC features click and pop reduction circuitry that minimizes audible popping during device turn-on and turn-off. The LM4663 is available in a 24-lead TSSOP package, ideal for portable and desktop computer applications. n n n n n n Efficiency at 2 Watt into 4Ω Efficiency at 250mW into 4Ω Total quiescent power supply current Total shutdown power supply current THD+N 1kHz, 20mW, 32Ω (Headphone) Single supply range 83% (typ) 69% (typ) 22mA (typ) 2µA (typ) 0.15% (typ) 4.5V to 5.5V Features n n n n n n Delta-sigma modulator. Two stereo input selector. “Click and pop”...