LT8551 Series

Multiphase Boost Converter Expander with Internal Gate Drivers

Catalog

Multiphase Boost Converter Expander with Internal Gate Drivers

Part	Output Configuration	Number of Outputs	Synchronous Rectifier	Mounting Type	Operating Temperature [Min]	Operating Temperature [Max]	Topology	Voltage - Input (Max) [Max]	Package / Case	Supplier Device Package	Voltage - Input (Min) [Min]	Frequency - Switching [Max]	Frequency - Switching [Min]	Output Type	Function
Analog Devices LT8551EUKG#PBF	Positive	1		Surface Mount	-40 °C	125 ¯C	Boost	80 V	52-WFQFN Exposed Pad	52-QFN (7x8)	3.6 V	1 MHz	100 kHz	Adjustable	Step-Up
Analog Devices LT8551IUKG#PBF	Positive	1		Surface Mount	-40 °C	125 ¯C	Boost	80 V	52-WFQFN Exposed Pad	52-QFN (7x8)	3.6 V	1 MHz	100 kHz	Adjustable	Step-Up

Catalog

Multiphase Boost Converter Expander with Internal Gate Drivers

Key Features

• Expands Up to 4 Phases per Chip

• Up to 80V Input or Output Voltage

• Cascade with Multiple Chips for High Current Applications

• Supports Up to 18 Distinct Phases from 20° to 180°

• Phases Can Share Phase Angle

• Excellent DC and Transient Current Sharing

• Phase-Lockable Fixed Frequency 125kHz to 1MHz

• Supports Bidirectional Current Flow

• RSENSEor DCR Current Sensing

• Eliminates the Need to Route Sensitive Feedback and Control Signals.

• 52-Lead (7mm × 8mm) QFN Package

Description

The LT8551 is a multiphase expander for synchronous boost DC/DC converters. It operates in tandem with any synchronous boost DC/DC converter to increase the load current capability by adding additional phases, which are clocked out-of-phase to reduce ripple current and filtering capacitance. It easily adds phases without the need to route sensitive feedback and control signals.The LT8551 integrates 5V gate drivers and can support up to four boost phases per device. Multiple LT8551 devices can be used for up to 18 phases. It accurately monitors and adjusts the current of each channel to achieve excellent DC and transient current sharing.The LT8551 operates over a fixed frequency from 100kHz to 1MHz or can be synchronized to an external clock.ApplicationsHigh Current Distributed Power SystemsTelecom, Datacom, and Storage SystemsIndustrial and Automotive