DESCRIPTION

The LTC®1735 is a synchronous step-down switching regulator controller that drives external N-channel power MOSFETs using a fixed frequency architecture. Burst ModeTM operation provides high efficiency at low load currents. The precision 0.8V reference is compatible with future generation microprocessors. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values.

FEATURES

■ Synchronizable/Programmable Fixed Frequency
■ OPTI-LOOPTM Compensation Minimizes COUT
■ ±1% Output Voltage Accuracy
■ Dual N-Channel MOSFET Synchronous Drive
■ Wide VIN Range: 4V to 36V Operation
■ VOUT Range: 0.8V to 6V
■ Internal Current Foldback
■ Output Overvoltage Crowbar Protection
■ Latched Short-Circuit Shutdown Timer
with Defeat Option
■ Very Low Dropout Operation: 99% Duty Cycle
■ Forced Continuous Control Pin
■ Optional Programmable Soft-Start
■ Remote Output Voltage Sense
■ Power Good Output (LTC1735F Only)
■ Logic Controlled Micropower Shutdown: IQ < 25µA
■ LTC1435 Pin Compatible with
Minor Component Changes
■ Available in 16-Lead Narrow SSOP, SO Packages and
20-Lead TSSOP Package (LTC1735F Only)

APPLICATIONS

■ Notebook and Palmtop Computers, PDAs
■ Cellular Telephones and Wireless Modems
■ DC Power Distribution Systems