The MPQ2143H is a monolithic, step-down, switch-mode converter with internal power MOSFETs. It can achieve up to 3A continuous output current from a 2.5V to 5.5V input voltage with excellent load and line regulation. The output voltage can be regulated as low as 0.6V. Constant-on-time control provides fast transient response and eases loop stabilization. Fault-condition protections include cycle-by-cycle current limiting and thermal shutdown. The MPQ2143H is available in small QFN-10 package and requires only a minimal number of readily-available standard external components. The MPQ2143H is ideal for a wide range of applications including high-performance DSPs, FPGAs, and portable instruments.