Prema 公司的PR4101是大功率LED降压驱动器，能串通方式驱动一个或多个大功率LED.工作电压可高达40V，采用外接N沟MOSFET开关管，输出电流可高达1A.可用于卤素灯，通用照明，告警照明，汽车照明，信号指示和LCD背景光.本文介绍了PR4101的主要特性， 方框图， 典型应用电路， 以及采用12/24V电源， 12VDC和12VAC电源的PR4101各种应用电路.

      High Power LED Buck Driver PR4101
      The PR4101 is a LED buck driver for driving one or several high power LEDs in series.
      The supply voltage can be up to 40V， with an output current of more than 1A using anexternal N-channel MOSFET switching transistor. The PR4101A with additional PWM andpower down input is delivered SOP14 packaged， while the PR4101B is offered SO8packaged.

      PR4101主要特性:
      Adjustable output current of 1A and more
      Supply voltage up to 40V bulb replacement by LEDs
      Dimming with phase-cut dimmer
      Brightness control with PWM (PR4101A only)
      Output current temperature compensation
      Delayed start possible (PR4101A only)
      Over temperature protection
      Frequency spreading for improved EMI
      Low standby current of < 35 μA
      Under voltage lockout

      应用:
      Halogen lamp or filament
      General illumination
      Warning lights
      Automotive lighting
      Indicator signs
      LCD backlighting

图1.PR4101典型应用电路

图2.PR4101方框图

图3.采用PR4101的12/24V电源的PR4101应用电路

图4.采用12VDC的PR4101应用电路图

图5.采用12VAC的PR4101应用电路

图6.PR4101显示板电路图