
Linear Technology
DESCRIPTIONS
The LT®3800 is a 200kHz fixed frequency high voltage synchronous current mode step-down switching regulator controller. The IC drives standard gate N-channel power MOSFETs and can operate with input voltages from 4V to 60V. An onboard regulator provides IC power directly from VIN and provides for output-derived power to minimize VIN quiescent current. MOSFET drivers employ an internal dynamic bootstrap feature, maximizing gate-source “ON” voltages during normal operation for improved operating efficiencies. The LT3800 incorporates Burst Mode®operation, which reduces no load quiescent current to under 100µA. Light load efficiencies are also improved through
FEATURES
■ Wide 4V to 60V Input Voltage Range
■ Output Voltages up to 36V
■ Adaptive Nonoverlap Circuitry Prevents Switch Shoot-Through
■ Reverse Inductor Current Inhibit for Discontinuous Operation Improves Efficiency with Light Loads
■ Output Slew Rate Controlled Soft-Start with Auto-Reset
■ 100µA No Load Quiescent Current
■ Low 10µA Current Shutdown
■ 1% Regulation Accuracy
■ 200kHz Operating Frequency
■ Standard Gate N-Channel Power MOSFETs
■ Current Limit Unaffected by Duty Cycle
■ Reverse Overcurrent Protection
■ 16-Lead Thermally Enhanced TSSOP Package
APPLICATIONS
■ 12V and 42V Automotive and Heavy Equipment
■ 48V Telecom Power Supplies
■ Avionics and Industrial Control Systems
■ Distributed Power Converters