LT3481

LT3481 36V, 2A, 2.8MHz Step-Down Switching Regulator with 50µA Quiescent Current FEATURES ■ Wide Input Range: 3.6V to 34V Operating, 36V Maximum ■ 2A Maximum Output Current ■ Low Ripple Burst Mode® Operation 50μA IQ at 12VIN to 3.3VOUT Output Ripple < 15mV ■ Adjustable Switching Frequency: 300kHz to 2.8MHz ■ Low Shutdown Current: IQ < 1μA ■ Integrated Boost Diode ■ Power Good Flag ■ Saturating Switch Design: 0.18Ω On-Resistance ■ 1.265V Feedback Reference Voltage ■ Output Voltage: 1.265V to 20V ■ Soft-Start Capability ■ Synchronizable Between 275kHz to 475kHz ■ Small 10-Pin Thermally Enhanced MSOP and (3mm x 3mm) DFN Packages APPLICATIONS ■ Automotive Battery Regulation ■ Power for Portable Products ■ Distributed Supply Regulation ■ Industrial Supplies ■ Wall Transformer Regulation DESCRIPTION The LT®3481 is an adjustable frequency (300kHz to 2.8MHz) monolithic buck switching regulator that accepts input voltages up to 34V (36V maximum). A high efficiency 0.18Ω switch is included on the die along with a boost Schottky diode and the necessary oscillator, control, and logic circuitry. Current mode topology is used for fast transient response and good loop stability. Low ripple Burst Mode operation maintains high efficiency at low output currents while keeping output ripple below 15mV in a typical application. In addition, the LT3481 can further enhance low output current efficiency by drawing bias current from the output when VOUT is above 3V. Shutdown reduces input supply curre...