The LTC3709 is a single output, dual phase, synchronous step-down switching regulator. The controller uses a constant on-time, valley current control architecture to deliver very low duty cycles without requiring a sense resistor. Operating frequency is selected by an external resistor and is compensated for variations in input supply voltage. An internal phase-locked loop allows the LTC3709 to be synchronized to an external clock. A TRACK pin is provided for tracking or sequencing the output voltage among several LTC3709 chips or an LTC3709 and other DC/DC regulators. Soft-start is accomplished using an external timing capacitor. Fault protection is provided by an output overvoltage comparator and an optional short-circuit shutdown timer. The current limit level is user programmable. A wide supply range allows voltages as high as 31V to step down to 0.6V. Protected by U.S. Patents, including 5481178, 6476589, 6144194, 5847554, 6177678, 6304066, 6580258, 6674274, 6462525, 6593724. Applications * Notebook Computers * Power Supply for DSP, ASIC, Graphic Processors * PolyPhase® Valley Current Mode Controller * Synchronizable to an External Clock with PLL * Coincident or Ratiometric Tracking * Sense Resistor Optional * 2% to 90% Duty Cycle at 200kHz * tON(MIN) < 100ns * True Remote Sensing Differential Amplifier * High Efficiency at Both Light and Heavy Loads * Power Good Output Voltage Monitor * 0.6V ±1% Reference * Adjustable Current Limit * Programmable Soft-Start and Operating Frequency * Output Overvoltage Protection * Optional Short-Circuit Shutdown Timer * 32-Lead (5mm × 5mm) QFN Package https://elecena.pl/product/258940/fast-2-phase-no-rsense-synchronous-dc-dc-controller-with-tracking-sequencing 2007-03-04 https://elecena.pl/product/258940/fast-2-phase-no-rsense-synchronous-dc-dc-controller-with-tracking-sequencing 2014-06-11 https://elecena.pl/product/258940/fast-2-phase-no-rsense-synchronous-dc-dc-controller-with-tracking-sequencing 2025-01-22