RT2853A Datasheet | Richtek

RT2853A/B 3A, 18V, 650k Hz, ACOT® Synchronous Step-Down Converter 1 General Description The RT2853A/B are high-performance 650k Hz 3A step- down regulators with internal power switches and synchronous rectifiers. They feature quick transient response using their Advanced Constant On-Time (ACOT® ) control architecture that provides stable operation with small ceramic output capacitors and without plicated external pensation, among other benefits. The input voltage range is from 4.5V to 18V and the output is adjustable from 0.765V to 7V. The proprietary ACOT® control improves upon other fast- response constant on-time architectures, achieving nearly constant switching frequency over line, load, and output voltage ranges. Since there is no internal clock, response to transients is nearly instantaneous and inductor current can ramp quickly to maintain output regulation without large bulk output capacitance. The RT2853A/B are stable with and optimized for ceramic output capacitors. With internal 110m switches and 30m synchronous rectifiers, the RT2853A/B display excellent efficiency and good behavior across a range of applications, especially for low output voltages and low duty cycles. Cycle-by- cycle current limit, input undervoltage lock-out, externally- adjustable soft-start, output under- and overvoltage protection, and thermal shutdown provide safe and smooth operation in all operating conditions. The RT2853A and RT2853B are each available in WQFN-16L 3x3 package, with exposed thermal pads. The remended junction temperature range is - 40C to 125C, and the ambient temperature range is - 40C to 85C. 2 Features - Fast Transient Response - Steady 650k Hz Switching Frequency - Enhanced Efficiency at Light Load (RT2853A) - Advanced Constant On-Time (ACOT®) Control - Optimized for Ceramic Output Capacitors - 4.5V to 18V Input Voltage Range - Internal 110m Switch and 30m Synchronous Rectifier - 0.765V to 7V Adjustable Output Voltage - Externally-adjustable,...