LTC3805

Features n VIN and VOUT Limited Only by External Components n Adjustable Slope Compensation n Adjustable Overcurrent Protection with Automatic Restart n Adjustable Operating Frequency (70kHz to 700kHz) with One External Resistor n Synchronizable to an External Clock n ±1.5% Reference Accuracy n Current Mode Operation for Excellent Line and Load Transient Response n RUN Pin with Precision Threshold and Adjustable Hysteresis n Programmable Soft-Start with One External Capacitor n Low Quiescent Current: 360µA n Small 10-Lead MSOP and 3mm × 3mm DFN Applications n Telecom Power Supplies n 42V and 12V Automotive Power Supplies n Isolated Electronic Equipment LTC3805 Adjustable Frequency Current Mode Flyback DC/DC Controller Description The LTC®3805 is a current mode controller for flyback DC/DC converters designed to drive an N-channel MOSFET in high input and output voltage converter applications. Operating frequency and slope compensation can be programmed by external resistors. Programmable overcurrent sensing protects the converter from short-circuits. Soft-start can be programmed using an external capacitor and the soft-start capacitor also programs an automatic restart feature. The LTC3805 provides ±1.5% output voltage accuracy and consumes only 360µA of quiescent current during normal operation and only 40µA during micropower startup. Using a 9.5V internal shunt regulator, the LTC3805 can be powered from a high VIN through a resistor or it can be powered directly from a low...