LM3743 - National Semiconductor

LM3743 N-Channel FET Synchronous Buck Controller

The LM3743 is a voltage mode PWM buck controller which implements synchronous rectification. It provides a low cost, fault tolerant, and efficient point of load solution. To reduce component count several parameters are fixed, such as switching frequency and the short circuit protection level. For example the LM3743 has an operating switching frequency of 30.

Features

1.6Ω of pull-up resistance and 1Ω of pull-down drive resistance for high power density and very efficient power processing. n Reference accuracy: ± 1.75%, over full temperature and input voltage range n Low-side sensing programmable current limit n Fixed high-side sensing for supplemental short-circuit protection n Undervoltage protection n Hiccup mode protection eliminates thermal runaway during fault conditions n Externally programmable soft-start with tracking capability n Switching frequency options of 1 MHz or 300 kHz n Pre-bias start-up capability n MSOP-10 package Applications n n n n .