The MAX8649 high-efficiency DC-to-DC step-down switching regulator delivers up to 1.8A of output current. The device operates from a 2.5V to 5.5V input voltage range, making it future proof for next-generation battery technologies. The output voltage is I2C programmable from 0.75V to 1.38V. Fully differential remote sense ensures precise DC regulation at the load. Total output error is less than 2% over load, line, and temperature.

The MAX8649 operates at a 3.25MHz fixed frequency. The high operating frequency minimizes the size of external components. The MAX8649 provides several features to minimize EMI of the DC-DC step-down converter. The switching frequency of the converter can be synchronized to the master clock of the application. When synchronizing to an external clock, the MAX8649 measures the frequency of the external clock to ensure that the clock is stable before changing the switching frequency to the external clock frequency.

An on-board DAC allows adjustment of the output voltage in 10mV steps. The output voltage can be programmed directly through the I2C interface, or by preloading a set of on-board registers and using the two VID logic signals to select the appropriate register. Other features include internal soft-start control circuitry to reduce inrush current, output overvoltage, overcurrent, and overtemperature protection.