LTC3865 Dual Synchronous Controllers


Linear Technology's dual, 2-phase synchronous DC/DC controllers with pin selectable outputs

Linear Technology's LTC3865 and LTC3865-1 are high performance dual synchronous step-down DC/DC switching regulator controllers that drive all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows a phase-lockable frequency of up to 770kHz. Power loss and noise are minimized by operating the two controller output stages out of phase.

OPTI-LOOP® compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. Independent track/soft-start pins for each controller ramp the output voltage during start up.

Current foldback limits MOSFET heat dissipation during short-circuit conditions. The MODE/PLLIN pin selects among Burst Mode® operation, pulse-skipping mode, and continuous inductor current mode. The output voltages can be precisely programmed by pin strapping or external resistors.

Features
  • Dual, 180° phased controllers
  • 2-Pin VID output voltage programming from 0.6V to 5V
  • High efficiency: up to 95%
  • RSENSE or DCR current sensing
  • Phase-lockable fixed frequency 250kHz to 770kHz
  • Adjustable current limit
  • Dual N-channel MOSFET synchronous drive
  • Wide Vin range: 4.5V to 38V operation
  • Adjustable soft-start current ramping or tracking
  • Output overvoltage protection with reverse current limit
  • Power good output voltage monitor
  • 32-pin 5mm x 5mm QFN and 38-lead TSSOP packages

LTC3865

Manufacturer Part Number Description Available Quantity Datasheets
LTC3865EFE#PBF IC REG CTRLR BUCK PWM CM 38TSSOP 337
LTC3865EUH#PBF IC REG CTRLR BUCK PWM CM 32-QFN 479
LTC3865EUH-1#PBF IC REG CTRLR BUCK PWM CM 32-QFN 338