资 源 简 介
The LM5027 pulse-width modulaTIon (PWM) controller containsall of the features necessary to implement power convertersuTIlizing the AcTIve Clamp / Reset technique. With theacTIve clamp technique, higher efficiencies and greater powerdensities can be realized compared to conventional catchwinding or RDC clamp / reset techniques. Three control outputsare provided: the main power switch control (OUTA), theactive clamp switch control (OUTB), and secondary side synchronousrectifier control (OUTSR). The timing between thecontrol outputs is adjustable with external resistors that programinternal precision timers. This controller is designed forhigh-speed operation including an oscillator frequency rangeup to 1 MHz and total PWM propagation delays less than 50ns. The LM5027 includes a high-voltage startup regulator witha maximum input voltage rating of 105V. Additional featuresinclude Line Under Voltage Lockout (UVLO), separate softstartof main and synchronous rectifier outputs, a timer forhiccup mode current limiting, a precision reference, and thermalshutdown.
