The MP2161A is a monolithic, step-down, switch-mode converter with built-in internal power MOSFETs. It achieves a 2A continuous output current from a 2.5V to 6V input voltage range with excellent load and line regulation. The output voltage is regulated as low as 0.6V. The constant-on-time (COT) control scheme provides fast transient response and eases loop stabilization. Fault condition protection includes cycle-by-cycle current limiting and thermal shutdown. The MP2161A is available in a small TSOT23-8 package and requires a minimum number of readily available, standard, external components. The MP2161A is ideal for a wide range of applications including high performance DSPs, FPGAs, PDAs, and portable instruments.