FEATURES
s s s s s s DESCRIPTIO s s s s s Wide Input Range: 5.5V to 60V 3A Peak Switch Current Small Thermally Enhanced 16-Pin TSSOP Package Constant 500kHz Switching Frequency Saturating Switch Design: 0.1Ω Peak Switch Current Maintained Over Full Duty Cycle Range Effective Supply Current: 2.5mA Shutdown Current: 30µA 1.2V Feedback Reference Voltage Easily Synchronizable Cycle-by-Cycle Current Limiting The LT ®3431 is a 500kHz monolithic buck switching regulator that accepts input voltages up to 60V. A high efficiency 3A, 0.1Ω switch is included on the die along with all the necessary oscillator, control and logic circuitry. A current mode architecture provides fast transient response and good loop stability. Special design techniques and a new high voltage process achieve high efficiency over a wide input range. Efficiency is maintained over a wide output current range by using the output to bias the circuitry and by utilizing a supply boost capacitor to saturate the power switch. Patented circuitry maintains peak switch current over the full duty cycle range.