The MPQ4433 is a synchronous, step-down, switching regulator with programmable frequency (350kHz to 2.5MHz) and integrated, internal, high-side and low-side power MOSFETs. The MPQ4433 provides up to 3A of highly efficient output current with current mode control for fast loop response. The wide 3.3V to 36V input range accommodates a variety of step-down applications in automotive input environments. The MPQ4433 is ideal for battery-powered applications due to its extremely low quiescent current. The MPQ4433 employs advanced asynchronous mode (AAM) to achieve high efficiency in light-load condition by scaling down the switching frequency to reduce switching and gate driving losses. Standard features include soft start, external clock synchronization, enable control, and power good indication. High-duty cycle and low dropout mode are provided for automotive cold-crank. Over-current protection (OCP) with valley-current detection is employed to prevent the inductor current from running away. Hiccup mode reduces the average current greatly in short-circuit condition. Thermal shutdown provides reliable and fault-tolerant operation. The MPQ4433 is available in a QFN-16 (3mmx4mm) package.