MP4571 Synchronous Buck Converter

The Monolithic Power Systems MP4571 fully integrated, fixed-frequency, synchronous step-down converter can achieve up to 1 A of continuous output current with peak current control for excellent transient response. The wide 4.5 V to 60 V input voltage range accommodates a variety of step-down applications in an automotive input environment. A 2 μA shutdown mode quiescent current makes it ideal for battery-powered applications. The MP4571 integrates internal high-side and low-side power MOSFETs for high efficiency without an external Schottky diode and is available in a 12-pin QFN package.

The MP4571 employs advanced asynchronous modulation (AAM), which achieves high efficiency during light load by scaling down the frequency to reduce the switching and gate driver losses. It offers standard features including built-in soft start, enable control, and a power good indicator. High duty cycle and low-dropout mode are provided for automotive cold crank conditions. In addition, the chip provides overcurrent protection (OCP) with valley current detection, which helps prevent current runaway. It also has hiccup short-circuit protection (SCP), input undervoltage lockout (UVLO), and auto-recovery thermal protection.

With internal compensation, the MP4571 offers a very compact solution with a minimum number of readily available, standard external components. It is available in a QFN-12 (2.5 mm x 3 mm) package.