LT3972

LT3972 33V, 3.5A, 2.4MHz Step-Down Switching Regulator with 75µA Quiescent Current FEATURES ■ Wide Input Range: Operation from 3.6V to 33V Overvoltage Lockout Protects Circuits Through 62V Transients ■ 3.5A Maximum Output Current ■ Low Ripple (<15mVP-P) Burst Mode® Operation: IQ = 75μA at 12VIN to 3.3VOUT ■ Adjustable Switching Frequency: 200kHz to 2.4MHz ■ Low Shutdown Current: IQ < 1μA ■ Integrated Boost Diode ■ Synchronizable Between 250kHz to 2MHz ■ Power Good Flag ■ Saturating Switch Design: 95mΩ On-Resistance ■ Output Voltage: 0.79V to 30V ■ Thermal Protection ■ Soft-Start Capability ■ Small 10-Pin Thermally Enhanced MSOP and (3mm × 3mm) DFN Packages APPLICATIONS ■ Automotive Battery Regulation ■ Distributed Supply Regulation ■ Industrial Supplies ■ Wall Transformer Regulation DESCRIPTION The LT®3972 is an adjustable frequency (200kHz to 2.4MHz) monolithic buck switching regulator that accepts input voltages up to 33V (62V maximum). A high efficiency 95mΩ 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 LT3972 can further enhance low output current efficiency by drawing bias current from the output when VOUT is above 3V. Shutdown reduces input supply curre...