LTC3873

LTC3873 No RSENSETM Constant Frequency Current Mode Boost/Flyback/SEPIC DC/DC Controller FEATURES n VIN and VOUT Limited Only by External Components n Internal or Programmable External Soft-Start n Constant Frequency 200kHz Operation n Adjustable Current Limit n Current Sense Resistor Optional n Maximum 60V on SW Node with RDS(ON) Sensing n ±1.5% Voltage Reference Accuracy n Current Mode Operation for Excellent Line and Load Transient Response n Low Quiescent Current: 300µA n Low Profile (1mm) ThinSOTTM and (0.75mm) 2mm × 3mm DFN Package APPLICATIONS n Telecom Power Supplies n 42V and 12V Automotive Power Supplies n Portable Electronic Equipment DESCRIPTION The LTC®3873 is a constant frequency current mode, boost, flyback or SEPIC DC/DC controller that drives an N-channel power MOSFET in high input and output voltage converter applications. Soft-start can be programmed using an external capacitor. The LTC3873 provides ±1.5% output voltage accuracy and consumes only 300μA quiescent current during normal operation and only 55μA during micropower start-up. Using a 9.3V internal shunt regulator, the LTC3873 can be powered from a high input voltage through a resistor or it can be powered directly from a low impedance DC voltage of 9V or less. The LTC3873 is available in 8-lead ThinSOT and 2mm × 3mm DFN packages. PARAMETER VCC UV+ VCC UV– LTC3873 8.4V 4V LTC3873-5 4.1V 2.9V L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. No RSENSE and ThinSOT...