5A Step-Down Converter with I²C Interface

The RT5735 device is a full featured 5.5V, 5A, synchronous step down constant-on-time (COT) current mode converter with two integrated MOSFETs. The RT5735 enables small designs by integrating the MOSFETs, implementing current mode control to reduce external component count, reducing inductor size by enabling up to 2.4MHz switching frequency, and minimizing the IC footprint with a small WL-CSP-20B 1.6x2 (BSC) package. The RT5735 provides accurate regulation for a variety of loads with an accurate ±1% Voltage Reference (VREF) over temperature. Efficiency is maximized through the integrated 34mΩ/18mΩ MOSFETs and 70μA typical quiescent current. Using the enable pin, shutdown supply current is less than 2μA by entering a shutdown mode.

The output voltage startup ramp is controlled by the slow start pin. An open-drain power good signal indicates the output is within 90% to 95% of its nominal voltage.