Demonstration circuit 556 is a high efficiency, high frequency buck converter, incorporating the LTC3414 monolithic synchronous regulator. The DC556 has an input voltage range of 2.5V to 5.5V and an output voltage range from 0.8V to 5V. The operating frequency range of the DC556 is either set with an external resistor or synchronized to an external clock, with a range between 300kHz and 4Mhz. Due to these features, the DC556 is ideal for Li-Ion battery voltage (2.7V to 4.2V) applications, such as PDAs, cellular phones, and digital cameras. DC556 can deliver high power – up to 4A of output current - in a relatively small circuit, thanks to 67milliohm high current power switches in the LTC3414. The LTC3414 also incorporates OPTI-LOOP compensation, so that the DC556 can be optimized to provide fast transient response over a wide range of line and load conditions. All these features make the DC556 perfectly suited for batter–powered, hand-held applications.