Micrel MIC4724 3A降压稳压方案

Micrel 公司的MIC4724是3A 2MHz降压开关稳压器,输入电压最大为6V.内部的低导通电阻P-MOSFET使得MIC4724获得92%以上的效率,最大占空比100%,输出`电压可调至1.0V,广泛应用在FPGA,DSP和ASIC,宽带通信,DVD/TV刻录机,通用点负载,打印机/扫描仪,机顶盒,计算机外设和视频卡上.本文介绍了MIC4724的主要特性,方框图, 典型应用电路以及输出电流3A的应用电路图和所用材料清单(BOM).同时还介绍了MIC4724YMME评估板电路图和相应的材料清单.

MIC4724 3A 2MHz Integrated Switch Buck Regulator with 6Vmax Input
The Micrel MIC4724 is a high efficiency PWM buck (step-down) regulator that provides up to 3A of output current. The MIC4724 operates at 2.0MHz and has proprietary internal compensation that allows a closed loop bandwidth of over 200KHz.
The low on-resistance internal p-channel MOSFET of the MIC4724 allows efficiencies over 92%, reduces external components count and eliminates the need for an expensive current sense resistor.
The MIC4724 operates from 3.0V to 6.0V input and the output can be adjusted down to 1V. The devices can operate with a maximum duty cycle of 100% for use in low-dropout conditions.
The MIC4724 is available in 10-pin ePAD MSOP package with a junction operating range from –40°C to +125°C.

MIC4724主要特性:
3.0 to 6.0V supply voltage
2.0MHz PWM mode
Output current to 3A
Up to 94% efficiency
100% maximum duty cycle
Adjustable output voltage option down to 1V
Ultra-fast transient response
Ultra-small external components Stable with a 1μH inductor and a 4.7μF output capacitor
Fully integrated 3A MOSFET switch
Micropower shutdown
Thermal shutdown and current limit protection
Pb-free 10-pin ePAD MSOP package
–40度C to +125度C junction temperature range

MIC4724主要应用:
FPGA/DSP/ASIC applications
General point of load
Broadband communications
DVD/TV recorders
Point of sale
Printers/Scanners
Set top boxes
Computing peripherals
Video cards



图1.MIC4724方框图



图2.MIC4724典型应用电路



图3.3A输出MIC4724电路图和材料清单(BOM)



MIC4724YMME评估板
The MIC4724 evaluation board requires an input power source that is able to deliver greater than 3V at over 3A. The output load can either be an active or passive load.



图4.MIC4724YMME评估板电路图
MIC4724YMME评估板材料清单(BOM):