Intersil ISL6726单端PWM控制解决方案
2011-05-16
作者:Intersil公司
Intersil公司的 ISL6726是适用于有源箝位正向转换器拓扑的单端PWM控制器,典型起动电流125uA,可调整峰值和平均限流保护,可调整软起动和软停止,具有精密的最大占空比和死区控制,内置超温保护,主要用在通信电源,AC/DC转换器以及电池充电器。本文介绍了ISL6726主要特性,方框图和典型应用电路。
The ISL6726 is a highly featured single-ended PWM controller intended for applications using the active clamp forward converter topology in either n- or p-channel active clamp
configurations, the asymmetric half-bridge topology, and the standard forward topologies with synchronous rectification. It is a current-mode PWM controller with many features designed to simplify its use. Among its many features are a precision oscillator which allows accurate control of the deadtime and maximum duty cycle, bi-directional synchronization with 180° phase shift for interleaving applications, adjustable soft-start and soft-stop, a low power disable mode, and average current limit for “brick-wall” overcurrent protection.
This advanced BiCMOS design features low start-up and operating currents, adjustable switching frequency to greater than 1MHz, high current FET drivers, and very low propagation delays for a fast response to overcurrent faults.
ISL6726主要特性:
• Precision Maximum Duty Cycle and Deadtime Control
• 125μA Typical Start-up Current
•Adjustable Peak and Average Current Limit Protection
•Programmable Oscillator Frequency
•Bi-Directional Synchronization with 180° Phase Shift for Interleaved Converter Applications
•Adjustable Soft-Start and Selectable Soft-Stop
•Selectable Minimum Duty Cycle Clamp for Synchronous Rectifier Applications
•Programmable Slope Compensation
•Supports N- and P-Channel Active Clamp FETs
•Programmable Switch Timing Between Main and Active Clamp Outputs
•Programmable Undervoltage Lock-Out (UV)
•Input Voltage Dependent Duty Cycle Clamp
•ENABLE Input with Low Power Disable
•Internal Over-Temperature Protection
•Pb-Free (RoHS Compliant)
ISL6726应用:
• Telecom and Datacom Power Supplies
• AC/DC Power Supplies
• Battery Chargers
图1。ISL6726方框图
图2。ISL6726典型应用电路:同步整流有源箝位正向
图3。ISL6726典型应用电路:二极管整流有源箝位正向
详情请见:
http://www.intersil.com/data/fn/fn7654.pdf