The MP9943 is a high-frequency, synchronous, rectified, step-down, switch-mode converter with built-in power MOSFETs. It offers a very compact solution to achieve a 3A peak output current with excellent load and line regulation over a wide input supply range. The MP9943 has synchronous mode operation for higher efficiency over the output current load range. Current-mode operation provides fast transient response and eases loop stabilization. Full protection features include over-current protection and thermal shutdown. The MP9943 requires a minimal number of readily-available standard external components, and is available in a space-saving QFN-8 (3mmx3mm) package.