原标题：IR IR3477高效15A直流电源解决方案

　　IR 公司的IR3477 SupIRBuckTM是容易使用的全集成高效DC/DC转换器,可提供输出电压精确控制的15A电流.输入电压3V-27V,输出电压0.5V-12V,其它特性还包括预偏置起动,非常精密的0.5V基准电源,欠压/过压关断,热保护,电源正常输出等.主要应用在笔记本和台式电脑,消费类电子如STB,LCD,TV和打印机,POL DC/DC转换器等.本文介绍了IR3477主要特性,方框图,演示板电路图和材料清单, IRDC3477 评估板主要特性,电路图和材料清单.

　　The IR3477 SupIRBuckTM is an easy‐to‐use, fully integrated and highly efficient DC/DC voltage regulator. The onboard constant on time hysteretic controller and MOSFETs make IR3477 a space‐efficient solution that delivers up to 15A of precisely controlled output voltage.

　　Programmable switching frequency, soft start, and thermally compensated over current protection allows for a very flexible solution suitable for many different applications and an ideal choice for battery powered applications.

　　Additional features include pre‐bias startup, very precise 0.5V reference, under/over voltage shutdown, thermal protection, power good output, and enable input with voltage monitoring capability.

　　IR3477主要特性:

　　Input Voltage Range: 3V to 27V

　　Output Voltage Range: 0.5V to 12V

　　Continuous 15A Load Capability

　　Constant On‐Time Control

　　Compensation Loop not Required

　　Excellent Efficiency at Very Low Output Currents

　　Programmable Switching Frequency and Soft Start

　　Thermally Compensated Over Current Protection

　　Power Good Output

　　Precision Voltage Reference (0.5V, +/‐1%)

　　Enable Input with Voltage Monitoring Capability

　　Pre‐bias Start Up

　　Thermal Shut Down

　　Under/Over Voltage Fault Protection

　　Forced Continuous Conduction Mode Option

　　Small, Low Profile 5mm x 6mm QFN Package

　　IR3477应用:

　　Notebook and Desktop Computers

　　Consumer Electronics – STB, LCD, TV, Printers

　　12V and 24V Distributed Power Systems

　　General Purpose POL DC‐DC Converters

　　Game Consoles and Graphics Cards

　　图1.IR3477功能方框图

　　图2.IR3477基本应用电路图

　　演示板材料清单(BOM):

　　IRDC3477 评估板主要特性:

　　VIN = +12V

　　VCC = +5V

　　VOUT = +1.05V

　　IOUT = 0 to 15A

　　FS = 300kHz @ CCM

　　L = 1μH

　　CIN = 22μF (ceramic 1210) + 68μF (electrolytic)

　　COUT = 47μF (ceramic 0805) + 330μF (PC-CON)

　　图4.IRDC3477 评估板连接框图

　　图5.IRDC3477 评估板电路图

　　IRDC3477 评估板材料清单: