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RT8249A/B/C
Dual-Channel Synchronous DC/DC Step-Down Controller with 5V/3.3V LDOs
General Description
The RT8249A/B/...
®
RT8249A/B/C
Dual-Channel Synchronous DC/DC Step-Down Controller with 5V/3.3V LDOs
General Description
The RT8249A/B/C is a dual-channel step-down, controller generating supply voltages for battery-powered systems. It includes two Pulse-Width Modulation (PWM) controllers adjustable from 2V to 5.5V, and two fixed 5V/3.3V linear
regulators. Each linear
regulator provides up to 100mA output current and 3.3V linear
regulator provides 1% accuracy under 35mA. The RT8249A/B has an oscillator output to driver the external charge pump application. The RT8249C provides a mode selection pin, SKIPSEL, to select Diode-Emulation Mode (DEM) or Audio Skipping Mode (ASM). Other features include on-board power-up sequencing, a power-good output, internal soft-start, and soft-discharge output that prevents negative voltage during shutdown.
A constant current ripple PWM control scheme operates without sense resistors and provides 100ns response to load transient. For maximizing power efficiency, the R...