24V Input, 500mA Buck Regulator with Dual-Input Power MUX

The MAX77756 is a synchronous 500mA step-down DC-DC converter with integrated dual-input power multiplexer (MUX). The converter operates on an input supply as low as 3.0V and as high as 24V. Default output voltage is factory-programmed to either 1.8V, 3.3V, or 5.0V. Output voltage is further adjustable through external resistors or an I2C serial interface.

The dual-input power MUX selects the higher voltage from two different input sources to power the step-down converter. Control circuitry ensures that only one channel of the MUX is on at a time to prevent cross-conduction between input sources. For single-input applications, the MUX can be bypassed and the step-down converter can be powered directly from the SUP pin.

The MAX77756 is available in a small 2.33mm × 1.42mm (0.7mm max height), 15-bump wafer-level package (WLP). For a similar buck converter without a power MUX, refer to the MAX77596.

Design Solution: Pack More Power in Your Cool, Small Smart-Home Hub ›

Applications

* Battery-Powered Systems, Backup Battery, Uninterruptible Rails * Home Automation, Low IQ Smart Hubs * Notebook and Tablet Computers * USB Type-C Power Delivery Accessories and Devices

* Wide Input Power Supply

* 3V to 24V Supply Voltage

* 500mA (max) Output Current

* 1.8V, 3.3V, or 5.0V Factory-Set VOUT with Optional I2C Control: 1.5V to 7.5V in 50mV Steps

* External Feedback Resistor VOUT Option (1V to 99% VSUP)

* Hardware or Software Enable

* Dual-Input Power MUX Replaces Common-Cathode Diode Arrays

* Automatic Ideal-Diode ORing Voltage Selector

* 250mΩ MOSFETs Minimize Power Consumption, BOM, and Solution Size

* Low IQ Enables Always-On Rails

* 1.5µA Quiescent Current (Only SUP Powered)

* 19µA Quiescent Current (IN1/IN2 Powered)

* 88% Peak Efficiency (12VSUP, 3.3VOUT)

* Safe and Easy to Use

* Short-Circuit and Thermal Protection

* 8ms Soft-Start

* Software-Enabled Spread Spectrum

* Pin-Programmable Inductor Peak Current Level

* Small Size

* 2.33mm × 1.42mm (0.7mm max height) Wafer-Level Package (WLP)

* 15-Bump, 0.4mm Pitch, 3 × 5 Array