IR采用IRS2540的IRPLLED1高压LED驱动方案

IR公司的IRS254(0,1)是高压(200 V (IRS2540)和600 V (IRS2541))高频降压恒流LED电流调整控制器,采用连续模式时延滞后降压稳压器,直接控制负载平均电流.起动电流小于500uA,140ns死区,片内基准电压±2%,频率高达500kHz.本文介绍了IRS254(0,1)的主要特性,方框图以及采用单个和两个MOSFET的IRS2540应用电路.同时还介绍了采用IRS2540的350mA 到1.5A高压LED驱动器IRPLLED1的电路图和所用材料清单.

The IRS254(0,1) are high voltage, high frequency buck control ICs for constant LED current regulation. They incorporate a continuous mode time-delayed hysteretic buck regulator to directly control the average load current, using an accurate on-chip bandgap voltage reference.

The application is inherently protected against short circuit conditions, with the ability to easily add opencircuit protection. An external high-side bootstrap circuit drives the buck switching element at high frequencies. A low-side driver is also provided for synchronous rectifier designs. All functions are realized within a simple 8 pin DIP or SOIC package.

IRS2540主要特性:

200 V (IRS2540) and 600 V (IRS2541) half bridge driver

Micropower startup (<500 μA)

±2% voltage reference

140 ns deadtime

15.6 V zener clamp on VCC

Frequency up to 500 kHz

Auto restart, non-latched shutdown

PWM dimmable..

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