PolyPhase Step-Down Synchronous Slave Controller with Sub-Milliohm DCR Sensing

The LTC3874 is a dual PolyPhase® current mode synchronous step-down slave controller. It enables high current, multi-phase applications when paired with a companion master controller by extending the phase count. Compatible master controllers include the LTC3884, LTC3866, LTC3877 and LTC3774. The LTC3874 employs a unique architecture that enhances the signal-to-noise ratio of the current sense signal, allowing the use of sub-milliohm DC resistance power inductors to maximize efficiency while reducing switching jitter. Its peak current mode architecture allows for accurate phase to phase current sharing even for dynamic loads.

Effectively working with a master controller, the LTC3874 supports all the programmable features as well as fault protection.

Applications

* High Current Distributed Power Systems

* Telecom, Datacom, and Storage Systems

* Intelligent Energy Efficient Power Regulation

* Phase Extender for High Phase Count Voltage Rails

* Accurate Phase-to-Phase Current Sharing

* Sub-Milliohm DCR Current Sensing

* Phase-Lockable Fixed Frequency 250kHz to 1MHz

* Immediate Response to Master IC's Fault

* Up to 12 Phase Operation

* Wide VIN Range: 4.5V to 38V

* VOUT Range:

* Up to 3.5V (LOWDCR Pin = INTVCC)

* Up to 5.5V (LOWDCR Pin = OV)

* Proprietary Current Mode Control Loop

* Programmable CCM/DCM Operation

* Programmable Phase Shift Control

* Dual N-Channel MOSFET Gate Drivers

* 28-Lead (4mm × 5mm) QFN Package