LM5027AMH/NOPB

TEXAS INSTRUMENTS  LM5027AMH/NOPB  芯片, 电压模式有源钳位控制器, 90V, 3A, TSSOP

The LM5027A is a functional variant of the LM5027 active clamp PWM controller. The functional difference of the LM5027A is that the maximum duty cycle of the LM5027A is decreased from 91% to 71%. In addition, the oscillator timing equation has been modified.

The LM5027A pulse-width modulation PWM controller contains all of the features necessary to implement power converters utilizing the Active Clamp / Reset technique. With the active clamp technique, higher efficiencies and greater power densities can be realized compared to conventional catch winding or RDC clamp / reset techniques. Three control outputs are provided: the main power switch control OUTA, the active clamp switch control OUTB, and secondary side synchronous rectifier control OUTSR. The timing between the control outputs is adjustable with external resistors that program internal precision timers. This controller is designed for high-speed operation including an oscillator frequency range up to 1 MHz and total PWM propagation delays less than 50 ns. The LM5027A includes a high-voltage startup regulator with a maximum input voltage rating of 105V. Additional features include Line Under Voltage Lockout UVLO, separate soft-start of main and synchronous rectifier outputs, a timer for hiccup mode current limiting, a precision reference, and thermal shutdown.