DESCRIPTION
The LTC®1553 is a high power, high efficiency switching regulator controller optimized for 5V or 12V input to 1.8V-3.5V output applications. It features a digitally programmable output voltage, a precision internal reference and an internal feedback system that provides output accuracy of ±1.5% at room temperature and typically±2% over-temperature, load current and line voltage shifts.

FEATURES
■ 5-Bit Digitally Programmable 1.8V to 3.5V Fixed
   Output Voltage
■ Provides All Features Required by the Intel
   Pentium® II Processor VRM 8.2 DC/DC
   Converter Specification
■ Flags for Power Good, Over-Temperature and
   Overvoltage Fault
■ 19A Output Current Capability from a 5V or 12V Supply
■ Dual N-Channel MOSFET Synchronous Driver
■ Initial Output Accuracy: ±1.5%
■ Excellent Output Accuracy: ±2% Typ Over Line,
   Load and Temperature Variations
■ High Efficiency: Over 95% Possible
■ Adjustable Current Limit Without External Sense
   Resistors
■ Fast Transient Response
■ Available in 20-Lead SSOP and SW Packages

APPLICATIONS
■ Power Supply for Pentium II, SPARC, ALPHA and
   PA-RISC Microprocessors
■ High Power 5V or 12V to 1.8V-3.5V Regulators