The MP28257 is a fully-integrated, synchronous, step-down, switch-mode converter with a programmable frequency. It offers a very compact solution that can provide up to 4A of continuous output current over a wide input supply range with excellent load and line regulation, and can operate at high efficiency over a wide output current load range. Constant-on-time control mode provides fast transient response and eases loop stabilization. Protections include short-circuit protection, over-current protection, over-voltage protection, under-voltage protection, and thermal shut down. The MP28257 requires a minimal number of readily-available standard external components.The device is available in a space saving 2mmx3mm QFN12 package that complies with ROHS.Wide 4.2V-to-20V Operating Input Range 4A Continuous Output Current Internal 120m? High-Side, 50m? LowSide Power MOSFETs Stable with Ceramic Output Capacitors Proprietary Switching Loss-Reduction Technology Power-Good Indicator Soft Startup/Shutdown Programmable Switching Frequency SCP, OCP, OVP, UVP Protection and Thermal Shutdown Output Adjustable from 0.815V to 13V Available in a 2mm x 3mm QFN12 Package