The LTC3719 is a 2-phase, VID programmable, synchronous step-down switching regulator controller that drives two N-channel external power MOSFET stages in a fixed frequency architecture. The 2-phase controller drives its two output stages out of phase at frequencies up to 300kHz to minimize the RMS ripple currents in both input and output capacitors. The 2-phase technique effectively multiplies the fundamental frequency by two, improving transient response while operating each channel at an optimum frequency for efficiency. Thermal design is also simplified. An operating mode select pin (FCB) can be used to select among three modes including Burst Mode operation for highest efficiency. An internal differential amplifier provides true remote sensing of the regulated supply’s positive and negative output terminals as required in high current applications. The RUN/SS pin provides soft-start and optional timed, short-circuit shutdown. Current foldback limits MOSFET dissipation during short-circuit conditions when the overcurrent latchoff is disabled. OPTI-LOOP compensation allows the transient response to be optimized for a wide range of output capacitors and ESR values. 2-Phase, High Efficiency, Step-Down Controller for AMD Opteron CPUs.
The LTC3719 is a 2‑phase, VID‑programmable synchronous step‑down switching regulator controller designed for high‑efficiency power conversion. It drives two external N‑channel MOSFETs and offers three operating modes: PWM, Burst and Cycle‑Skip, with programmable fixed‑frequency operation from 150 kHz to 300 kHz.
Key features include true remote‑sensing differential amplification, power‑good monitoring, current‑mode control for current sharing, and adjustable soft‑start ramping. The device is supplied in a 36‑lead narrow SSOP package and is intended for server and workstation power supplies, especially AMD Opteron CPUs.
| Output Voltage Range | 0.8 V to 1.55 V |
|---|---|
| Input Supply Voltage Range | 3.6 V to 30 V |
| Programmable Switching Frequency | 150 kHz to 300 kHz |
| Maximum Output Current | 3 A |
| Package Type | 36‑Lead Plastic SSOP |
The LTC3719 can regulate an output voltage from 0.8 V up to 1.55 V.
The device supports a programmable fixed switching frequency between 150 kHz and 300 kHz.
The LTC3719 is supplied in a 36‑lead narrow SSOP package.