9A, 6.5V, 1MHz, ACOT^® Synchronous Step-Down Converter with I²C Interface

The RT5759A is a high-performance, synchronous step-down DC-DC converter that can deliver up to 9A output current from a 3V to 6.5V input supply. The output voltage can be programmable from 0.6V to 1.725V with I²C controlled 7-Bits VID.

The device integrates low R_DS(ON) power MOSFETs, accurate 0.6V reference and an integrated diode of bootstrap circuit to offer a very compact solution.

The RT5759A adopts Advanced Constant On-Time (ACOT^®) control architecture that provides ultrafast transient response and further reduce the external-component count. In steady states, the ACOT^® operates in nearly constant switching frequency over line, load and output voltage ranges and makes the EMI filter design easier. The RT5759A offers automatic PSM that maintains high efficiency during light load operation. The RT5759A can also operate in Forced-CCM through I²C setting that helps meet tight voltage regulation accuracy requirements.

The device offers a variety of functions for more design flexibility. The switching frequency, current limit level and over temperature threshold are selectable via I²C. Independent enable control input pin and power good indicator are also provided for easy sequence control. Besides, the designers can also command the device to be enabled or shutdown via the I²C interface.

The device offers Independent enable control input pin and power good indicator for easily sequence control. To control the inrush current during the startup, the device provides a programmable soft-start up by an external capacitor connected to the SS pin. Fully protection features are also integrated in the device including the cycle-by-cycle current limit control, UVP, input UVLO and OTP.

The RT5759A is available in a thermally enhanced UQFN-13L 3x3 (FC) package. The recommended junction temperature range is -40°C to 125°C, and the ambient temperature range is -40°C to 85°C.