LTC1701B

` Tiny 5-Lead SOT-23 Package
` Uses Tiny Capacitors and Inductor
` High Frequency Operation: 1MHz
` High Output Current: 500mA
` Low R<sub>DS(ON)</sub> Internal Switch: 0.28
` High Efficiency: Up to 94%
` Current Mode Operation for Excellent Line and Load Transient Response
` Short-Circuit Protected
` Low Quiescent Current: 135mA (LTC1701)
` Low Dropout Operation: 100% Duty Cycle
` Ultralow Shutdown Current: I<sub>Q</sub> < 1A
` Peak Inductor Current Independent of Inductor Value
` Output Voltages from 5V Down to 1.25V

· PDAs/Palmtop PCs
· Digital Cameras
· Cellular Phones
· Portable Media Players
· PC Cards
· Handheld Equipment

(Voltages Referred to GND Pin)
V_IN Voltage (Pin 5)...........................................0.3V to 6V
I_TH/RUN Voltage (Pin 4) ...................................0.3V to 3V
V_FB Voltage (Pin 3) ...........................................0.3V to 3V
V_IN SW (Max Switch Voltage) ....................8.5V to 0.3V
Operating Temperature Range (Note 2) .. 40°C to 85°C
Junction Temperature (Note 5) ................................ 125°C
Storage Temperature Range .................. 65°C to 150°C
Lead Temperature (Soldering, 10 sec)...................... 300°C

The LTC^®1701/LTC1701B are the industry's first SOT-23 step-down, current mode, DC/DC converters. Intended for low to medium power applications, they operate from 2.5V to 5.5V input voltage range and switch at 1MHz, allowing the use of tiny, low cost capacitors and inductors 2mm or less in height. The output voltage is adjustable from 1.25V to 5V. A built-in 0.28 switch allows up to 0.5A of output current at high efficiency. OPTI-LOOP^TM compensation allows the transient response to be optimized over a wide range of loads and output capacitors.

The LTC1701 incorporates automatic power saving Burst Mode^TM operation to reduce gate charge losses when the load current drops below the level required for continuous operation. The LTC1701B operates continuously to very low load currents to provide low ripple at the expense of light load efficiency. With no load, the LTC1701 draws only 135A. In shutdown, both devices draw less than 1A, making them ideal for current sensitive applications.