LM4675 Datasheet | National Semiconductor

Description Key Specifications The LM4675 is a single supply, high efficiency, 2.65W, mono, j Efficiency at 3.6V, 400m W into 8Ω speaker 89% (typ) Class D audio amplifier. A spread spectrum, filterless PWM j Efficiency at 3.6V, 100m W into 8Ω speaker 80% (typ) architecture reduces EMI and eliminates the output filter, j Efficiency at 5V, 1W into 8Ω speaker 89% (typ) reducing external ponent count, board area consumption, system cost, and simplifying design. j Quiescent current, 3.6V supply 2.2m A (typ) The LM4675 is designed to meet the demands of mobile j Total shutdown power supply current 0.01µA (typ) phones and other portable munication devices. Operatj Single supply range 2.4V to 5.5V ing on a single 5V supply, it is capable of driving a 4Ω j PSRR, f = 217Hz 82d B speaker load at a continuous average output of 2.2W with less than 1% THD+N. Its flexible power supply requirements allow operation from 2.4V to 5.5V. The wide band spread Features spectrum architecture of the LM4675 reduces EMI-radiated n Spread spectrum architecture reduces EMI emissions due to the modulator frequency. n Mono Class D Operation The LM4675 has high efficiency with speaker loads n No output filter required for inductive loads pared to a typical Class AB amplifier. With a 3.6V supply driving an 8Ω speaker, the IC’s efficiency for a 100m W n Externally configurable gain power level is 80%, reaching 89% at 400m W output power. n Very fast turn on time: 17µs (typ) The LM4675 features a low-power consumption shutdown n Minimum external ponents mode. Shutdown may be enabled by driving the Shutdown n "Click and pop" suppression circuitry pin to a logic low (GND). n Micro-power shutdown mode The gain of the LM4675 is externally configurable which . n Available in space-saving 0.5mm pitch micro SMD and allows independent gain control from multiple sources by LLP packages summing the signals. Output short circuit and thermal overload protection prevent the device from damage during fault Applications...