LM4817 Datasheet | National Semiconductor

Description The LM4817 bines a bridge-connected (BTL) stereo audio power amplifier with a low dropout voltage regulator (LDO). The audio amplifier delivers 1.0W to a 8Ω load with a less than 1.0% THD+N while operating on a 5V power supply. With VLIM set to 1.0V, the amplifier outputs are clamped to 6Vp-p, ± 800m V. With the LM4817’s adjustable low-dropout (LDO) CMOS linear regulator delivers an output current of up to 300m A, has shutdown mode (1n A, typ) low quiescent current (90µA, typ) and LDO voltage (120m V, typ). The regulator is stable with small ceramic capacitive load (2.2µF, typ). The regulator includes regulation fault detection, a bandgap voltage reference, and constant current limiting. It is designed for low power, low current applications that can take advantage of its 300m A output current capability. The LM4817 features an externally controlled micropower shutdown mode and thermal shutdown protection. It also utilizes circuitry that reduces "clicks and pops" during device turn-on and return from shutdown. Boomer audio power amplifiers are designed specifically to use few external ponents and provide high quality output power in a surface mount package. Key Specifications n n n n n n n n n n n PO (BTL): VDD = 5V, THD+N ≤ 1%, RL = 8Ω 1.0W(typ) Power supply range (amplifier) 3.0V to 5.5V Power supply range (LDO) 2.5V to 6.0V Shutdown current 0.07µA (typ) LDO output current 300m A (min) LDO dropout voltage (IOUT = 300m A) 120m V (typ) LDO quiescent supply current 90µA (typ) LDO shutdown supply current 1n A (typ) LDO PSRR 60d B LDO turn-on time 120ms (typ) LDO ouput noise-voltage 37µVRMS (typ) Features n n n n n n n n n Stereo BTL amplifier Adjustable output voltage magnitude limiter Adjustable LDO regulator “Click and pop” suppression circuitry LDO is stable with small-value ceramic output capacitors Unity-gain stable audio amplifiers LDO has over-current protection Thermal shutdown protection circuitry TSSOP (MH) package Applications n Multimedia monitors n...