The TPS56221 device is a high-efficiency and high-current synchronous buck converter
designed to operate from a supply from 4.5 V to 14 V. The device can produce an output voltage as
low as 0.6 V at loads up to 25 A. Integrated NexFET™ Power MOSFETs
provide a small footprint and ease of use.
The device implements a voltage-mode control with voltage feed-forward compensation that
responds instantly to input voltage change.
The TPS56221 is available in a thermally enhanced 22-pin PQFN (DQP) PowerPAD package.
The device offers design flexibility with a variety of user programmable functions,
including soft-start, overcurrent protection (OCP) levels, and loop compensation. OCP levels are
programmed by a single external resistor connected from the ILIM pin to the circuit ground. During
the initial power-on sequence, the device enters a calibration cycle, measures the voltage at the
ILIM pin, and sets an internal OCP voltage level. During operation, the programmed OCP voltage
level is compared to the voltage drop across the low-side FET when it is on to determine whether
there is an overcurrent condition. It then enters a shutdown/restart cycle until the fault is