High Efficiency SO-8 N-Channel Switching Regulator Controller

The LTC1624 is a current mode switching regulator controller that drives an external N-channel power MOSFET using a fixed frequency architecture. It can be operated in all standard switching configurations including boost, step-down, inverting and SEPIC. Burst Mode™ operation provides high efficiency at low load currents. A maximum high duty cycle limit of 95% provides low dropout operation which extends operating time in battery-operated systems.

The operating frequency is internally set to 200kHz, allowing small inductor values and minimizing PC board space. The operating current level is user-programmable via an external current sense resistor. Wide input supply range allows operation from 3.5V to 36V (absolute maximum).

A multifunction pin (ITH/RUN) allows external compensation for optimum load step response plus shutdown. Soft start can also be implemented with the ITH/RUN pin to properly sequence supplies.

Applications

* Notebook and Palmtop Computers, PDAs

* Cellular Telephones and Wireless Modems

* Battery-Operated Digital Devices

* DC Power Distribution Systems

* Battery Chargers

* N-Channel MOSFET Drive

* Implements Boost, Step-Down, SEPIC and Inverting Regulators

* Wide VIN Range: 3.5V to 36V Operation

* Wide VOUT Range: 1.19V to 30V in Step-Down Configuration

* ±1% 1.19V Reference

* Low Dropout Operation: 95% Duty Cycle

* 200kHz Fixed Frequency

* Low Standby Current

* Very High Efficiency

* Remote Output Voltage Sense

* Logic-Controlled Micropower Shutdown

* Internal Diode for Bootstrapped Gate Drive

* Current Mode Operation for Excellent Line and Load Transient Response

* Available in an 8-Lead SO Package