LTC3561A

FEATURES ■ Uses Tiny Capacitors and Inductor ■ High Frequency Operation: Up to 4MHz ■ Low RDS(ON) Internal Switches: 0.15Ω ■ High Efficiency: Up to 96% ■ Stable with Ceramic Capacitors ■ Current Mode Operation for Excellent Line and Load Transient Response ■ Short-Circuit Protected ■ Low Dropout Operation: 100% Duty Cycle ■ Low Shutdown Current: IQ ≤ 1µA ■ Low Quiescent Current: 330µA ■ Output Voltages from 0.8V to 5V ■ VIN: 2.5V to 5.5V ■ Small 8-Lead 3mm × 3mm DFN Package APPLICATIONS ■ Notebook Computers ■ Digital Cameras ■ Cellular Phones ■ Handheld Instruments ■ Board Mounted Power Supplies LTC3561A 1A, 4MHz, Synchronous Step-Down DC/DC Converter DESCRIPTION The LTC®3561A is a constant frequency, synchronous step-down DC/DC converter. Intended for medium power applications, it operates from a 2.5V to 5.5V input voltage range and has a user configurable operating frequency up to 4MHz, allowing the use of tiny, low cost capacitors and inductors 1mm or less in height. The output voltage is adjustable from 0.8V to 5.5V. Internal synchronous power switches provide high efficiency. The LTC3561A’s current mode architecture and external compensation allow the transient response to be optimized over a wide range of loads and output capacitors. To further maximize battery life, the P-channel MOSFET is turned on continuously in dropout (100% duty cycle). In shutdown, the device draws <1µA. L, LT, LTC, LTM, Linear Technology, the Linear logo and OPTI-LOOP are registered trademarks ...