The MP2131 is a monolithic step-down, switchmode converter with built-in internal power MOSFETs. It achieves a 4 A continuous output current from a 2.7 V to 5.5 V input voltage with excellent load and line regulation. The MP2131 is ideal for powering portable equipment that run from a single cell lithium-ion (Li+) battery. The output voltage is regulated as low as 0.6 V. The constant-on-time (COT) control scheme provides fast transient response, high light-load efficiency, and eases loop stabilization. Fault condition protection includes cycle-by-cycle current limit and thermal shutdown. The MP2131 requires a minimum number of readily available, standard, external components and is available in an ultra-small QFN-12 (2mm x 2mm) package. The MP2131 is ideal for a wide range of applications including portable instruments, small handheld and battery–powered devices, PDAs, and DVD drives.Wide 2.7 V to 5.5 V Operating Input Range Output Voltage as Low as 0.6 V 4 A Output Current 35 m? and 18 m? Internal Power MOSFET Above 96% Peak Efficiency Above 80% Light Load Efficiency Low IQ: 19 µA 1.2 MHz Frequency 100% Duty Cycle in Dropout 0.5 ms Internal Soft-Start Time EN and Power Good for Power Sequencing Auto Discharge at EN Off Short-Circuit Protection with Hiccup Mode Available in a QFN-12 (2mm x 2mm) Package