Richtek RT6237B

Description

The RT6237A/B is a high-performance 500kHz, 7A stepdownregulator with internal power switches andsynchronous rectifiers. It features quick transient responseusing its Advanced Constant On-Time (ACOTTM) controlarchitecture that provides stable operation with smallceramic output capacitors and without complicatedexternal compensation, among other benefits. The inputvoltage range is from 4.5V to 18V and the output isadjustable from 0.7V to 8V. The proprietary ACOTTM controlimproves upon other fast response constant on-timearchitectures, achieving nearly constant switchingfrequency over line, load, and output voltage ranges. Sincethere is no internal clock, response to transients is nearlyinstantaneous and inductor current can ramp quickly tomaintain output regulation without large bulk outputcapacitance. The RT6237A/B is stable with and optimizedfor ceramic output capacitors. With internal 40mΩ switchesand 16mΩ synchronous rectifiers, the RT6237A/B displaysexcellent efficiency and good behavior across a range ofapplications, especially for low output voltages and lowduty cycles. Cycle-by-cycle current limit providesprotection against shorted outputs, input under-voltagelockout, externally-adjustable soft-start, output under- andover-voltage protection, and thermal shutdown provide safeand smooth operation in all operating conditions. TheRT6237A/B is available in the UQFN-14L 2x3 (FC)package, with exposed thermal pad.

Features

• Fast Transient Response
• Advanced Constant On-Time (ACOTTM) Control
• 4.5V to 18V Input Voltage Range
• Adjustable Output Voltage from 0.7V to 8V
• 7A Output Current
• 40mΩ Internal High-Side N-MOSFET and 16mΩ
• Internal Low-Side N-MOSFET
• Steady 500kHz Switching Frequency
• Up to 95% Efficiency
• Optimized for All Ceramic Capacitors
• Externally-Adjustable, Pre-Biased Compatible Soft-Start
• Cycle-by-Cycle Current Limit
• Input Under-Voltage Lockout
• Output Over- and Under-Voltage Protection
• Power Good Output
• Thermal Shutdown

Typical applications

• Point of Load Regulation for High-Performance DSPs, FPGAs, and ASICs
• Industrial and Commercial Low Power Systems
• Green Electronics/Appliances
• Computer Peripherals / LCD Monitors and TVs

More information

• Datasheet