LTC3733-1 Datasheet | Linear Technology

LTC3733/LTC3733-1 3-Phase, Buck Controllers for AMD CPUs Features s s s s DESCRIPTIO s s s s s s s s s s s s s U APPLICATIO S s s 3-Phase Controller with Onboard MOSFET Drivers Current Mode Control Ensures Current Sharing Differential Amplifier Accurately Senses VOUT ±5% Output Current Matching Optimizes Thermal Performance and Size of Inductors and MOSFETs Reduced Input and Output Capacitance Supports Active Voltage Positioning VID Programmable Output Voltage from 0.8V to 1.55V (AMD Opteron TM CPU) 6-Phase, 90A to 120A Operation Output Power Good Indicator with Adaptive Blanking 210k Hz to 530k Hz Per Phase, PLL, Fixed Frequency Synchronizable (LTC3733-1) PWM, Stage Shedding or Burst Mode® Operation OPTI-LOOP® pensation Minimizes COUT Adjustable Soft-Start Current Ramping Short-Circuit Shutdown Timer with Defeat Option No_CPU Detection 36-Lead 0.209" SSOP and 38-Lead (5mm × 7mm) QFN The LTC®3733 family are Poly Phase® synchronous stepdown switching regulator controllers that drive all N-channel external power MOSFET stages in a phaselockable, fixed frequency architecture. The 3-phase controller drives its output stages with 120° phase separation at frequencies of up to 530k Hz per phase to minimize the RMS current dissipated by the ESR of both the input and output filter capacitors. The 3-phase technique effectively triples the fundamental frequency, improving transient response while operating each phase at an optimal frequency for efficiency and ease of thermal design. Light load efficiency is optimized by using a choice of output stage shedding or Burst Mode technology. A differential amplifier provides true remote sensing of both the high and low sides of the output voltage at load points. Soft-start and a defeatable, timed short-circuit shutdown protect the MOSFETs and the load. A foldback current circuit also provides protection for the external MOSFETs under short-circuit or overload conditions. An all-“1” VID detector turns off the regulator after 1µs...