The LTC3809-1 is a synchronous step-down switching regulator controller that drives external complementary power MOSFETs using few external components. The constant frequency current mode architecture with MOSFET VDS sensing eliminates the need for a current sense resistor and improves efficiency. Optional Burst Mode operation provides high efficiency operation at light loads. 100% duty cycle provides low dropout operation, extending operating time in battery-powered systems. Burst Mode is inhibited when the MODE pin is pulled low to reduce noise and RF interference. The LTC3809-1 allows either coincident or ratiometric output voltage tracking. Switching frequency is fixed at 550kHz. Fault protection is provided by an overvoltage comparator and a short-circuit current limit comparator. The LTC3809-1 is available in tiny footprint thermally enhanced DFN and 10-lead MSOP packages. Features Package LTC3809 PLL, Selectable Spread Spectrum, Power Good 3x3 DFN-10, MS-10E LTC3809-1 Tracking 3x3 DFN-10, MS-10E LTC3808 PLL, Selectable Spread Spectrum, Tracking, Power Good 4x3 DFN-14, SSOP-16 Applications * 1- or 2-Cell Lithium-Ion Powered Devices * Notebook and Palmtop Computers, PDAs * Portable Instruments * Distributed DC Power Systems * Programmable Output Voltage Tracking * No Current Sense Resistor Required * Constant Frequency Current Mode Operation for Excellent Line and Load Transient Response * Wide VIN Range: 2.75V to 9.8V * Wide VOUT Range: 0.6V to VIN * 0.6V ±1.5% Reference * Low Dropout Operation: 100% Duty Cycle * Selectable Burst Mode®/Pulse-Skipping/Forced Continuous Operation https://elecena.pl/product/259849/no-r-low-input-voltage-synchronous-dc-dc-controller-with-output-tracking 2007-03-04 https://elecena.pl/product/259849/no-r-low-input-voltage-synchronous-dc-dc-controller-with-output-tracking 2017-10-11 https://elecena.pl/product/259849/no-r-low-input-voltage-synchronous-dc-dc-controller-with-output-tracking 2025-01-19