MAX25431 H-Bridge Buck-Boost Controller

Analog Devices' MAX25431is a current‐mode buck‐boost controller. The device operates with input voltages from 4.5 V to 36 V while using only 55 µA quiescent current at no load. The wide input voltage range, along with its ability to maintain constant output voltage during battery transients, makes the device ideal for automotive applications. Once the start‐up conditions are satisfied, the device can operate over an extended input voltage range of 2 V to 36 V. The switching frequency is resistor programmable from 220 kHz to 2.2 MHz and can be synchronized to an external clock.

The device output voltage is available as 5 V fixed or adjustable from 4 V to 25 V. In light load applications, a logic input (FSYNC) allows the devices to operate either in skip mode for reduced current consumption, or fixed‐frequency, forced‐PWM mode to eliminate frequency variation and help minimize EMI. Protection features include cycle‐by‐cycle current limit and thermal shutdown with automatic recovery.

The MAX25431 is available in a small 4 mm x 4 mm 24-pin TQFN-EP SW package.