原标题：Intersil ISL8018低静态电流8A高效降压电源解决方案

　　Intersil公司的ISL8018是低静态电流8A高效同步降压电源稳压器,输出电压2.7V-5.5V,输出电压从0.6V到VIN可调,效率高达97%,可调频率从500kHz到4MHz,在不能时软起动放电,8A输出电流压降250mV,主要用在DC/DC POL模块,μC/μP, FPGA和 DSP电源,路由器和交换机插入DC/DC模块,手持仪表,测量和测试系统以及用锂电池的设备.本文介绍了ISL8018主要特性,框图,应用电路,以及演示板ISL8018DEMO1Z主要特性,框图,电路图,材料清单和PCB设计图.

　　The ISL8018 is a high efficiency, monolithic, synchronousstep-down DC/DC converter that can deliver up to 8A continuousoutput current from a 2.7V to 5.5V input supply. The outputvoltage is adjustable from 0.6V to VIN. With an adjustable currentlimit, reverse current protection, prebias start andover-temperature protection, the ISL8018 offers a highly robustpower solution. It uses current control architecture to deliver fasttransient response and excellent loop stability.

　　The ISL8018 integrates a pair of low ON-resistance P-channeland N-channel internal MOSFETs to maximize efficiency andminimize external component count. 100% duty-cycle operationallows less than 250mV dropout at 8A output current. Adjustable frequency and synchronization allow the ISL8018 to be used inapplications requiring low noise.

　　The ISL8018 can be configured for discontinuous or forcedcontinuous operation at light load. Forced continuous operationreduces noise and RF interference while discontinuous modeprovides high efficiency by reducing switching losses at light loads.

　　The ISL8018 is offered in a space saving 20 Ld 3x4 QFN lead freepackage with exposed pad lead frames for excellent thermalperformance. The complete converter occupies less than96.8mm2 area.

　　ISL8018主要特性:

　　• High efficiency synchronous buck regulator with up to 97%efficiency

　　• ±10% output voltage margining

　　• Adjustable current limit

　　• Start-up with prebiased output

　　• Internal soft-start - 1ms or adjustable, internal/externalcompensation

　　• Soft-stop output discharge during disabled

　　• Adjustable frequency from 500kHz to 4MHz - default at 1MHz

　　• External synchronization up to 4MHz - master to slave phaseshifting capability

　　• Peak current limiting, hiccup mode short-circuit protection andover-temperature protection

　　ISL8018应用:

　　• DC/DC POL modules

　　• μC/μP, FPGA and DSP power

　　• Plug-in DC/DC modules for routers and switchers

　　• Portable instruments

　　• Test and measurement systems

　　• Li-ion battery powered devices

　　图1.ISL8018框图

　　图2.ISL8018单片8A应用兵电路图

　　演示板ISL8018DEMO1Z

　　The ISL8018DEMO1Z is intended for use by individuals withrequirements for point-of-load applications sourcing from 2.7Vto 5.5V. The ISL8018DEMO1Z simple, small form factordemonstration board is used for a quick and easydemonstration of the performance of the ISL8018 lowquiescent, high efficiency synchronous buck regulator.

　　The ISL8018DEMO1Z is a 20.07mmx16.51mm 4-layer FR4board with 2oz copper in all layers. The complete converteroccupies 115.613mm2 area.

　　演示板ISL8018DEMO1Z主要特性:

　　• High efficiency synchronous buck regulator with up to 97%efficiency

　　• ±10% output voltage margining

　　• Adjustable current limit

　　• Start-up with prebiased output

　　• Internal soft-start - 1ms or adjustable

　　• Soft-stop output discharge while disabled

　　• Adjustable frequency from 500kHz to 4MHz - default at 1MHz

　　• External synchronization up to 4MHz - master to slave phaseshifting capability

　　图3.演示板ISL8018DEMO1Z框图

　　图4.演示板ISL8018DEMO1Z外形图

　　图5.演示板ISL8018DEMO1Z电路图

　　演示板ISL8018DEMO1Z材料清单:

　　详情请见:

isl8018demo1z-user-guide.pdf

isl8018.pdf