LTC7149, 60 V, 4 A Synchronous Buck for Inverting Outputs

Analog Devices' LTC7149 is a high-efficiency, 60 V, 4 A synchronous monolithic step-down regulator for inverting output applications. The regulator features a single resistor programmable output voltage and high efficiency over a wide V_OUT range.

The inverting regulator operates from an input voltage range of 3.4 V to 60 V and provides an adjustable output from -28 V to 0 V while delivering up to 4 A of inductor current. The switching frequency is also set with an external resistor. A user-selectable mode input is provided to allow the user to trade-off ripple noise for efficiency at light loads; burst mode operation provides the highest efficiency at light loads, while forced continuous mode provides low output ripple. The MODE / SYNC pin can also be used to synchronize the switching frequency to an external clock. Internal level-shift circuits allow the I/O pins (RUN, MODE / SYNC, and PGOOD) to be referenced to board GND.

Design Note: Inverting Regulator Takes Inputs Up to 50 V and Supports Outputs to 4 A