100-V synchronous buck DC/DC controller with wide duty-cycle range

The LM5146

100-V synchronous buck

controller regulates from a high input voltage source or from an input rail subject

to high-voltage transients, minimizing the need for external surge suppression

components. A high-side switch minimum on-time of 40 ns gives large step-down

ratios, enabling the direct step-down conversion from a 48-V nominal input to

low-voltage rails for reduced system complexity and solution cost. The LM5146 continues to operate during input voltage dips

as low as 5.5 V, at nearly 100% duty cycle if needed, making it an excellent choice

for high-performance industrial controls,

robotics, datacom, and RF applications.

Forced-PWM (FPWM) operation eliminates switching frequency variation to minimize EMI, while user-selectable diode emulation lowers current consumption at light-load conditions. The adjustable switching frequency as high as 1 MHz can be synchronized to an external clock source to eliminate beat frequencies in noise-sensitive applications.