4-Phase DC-DC Expander with Internal Gate Drivers for Buck Converters
The LT®8550 from Analog Devices is a multiphase expander for synchronous buck dc-dc converters. It operates in tandem with any buck 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 LT8550 integrates gate drivers and can support up to four buck phases per device.
Targeted applications include; high-current distributed power systems, telecom, datacom and storage systems, and general industrial and automotive applications.
Recommended for you: 18V 2A, and 3A Buck Regulators in Thermally-Enhanced Package
Multiple LT8550's 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 LT8550 operates over a fixed frequency from 100kHz to 1MHz, or can be synchronized to an external clock.
LT8550 typical application (click on image to enlarge)
Summary of Features:
- Expands Up to Four Phases per Chip
- Up to 80V Input or Output Voltage
- Cascade with Multiple Chips for Very High Current Applications
- Supports Up to 18 Distinct Phases from 20° to 180° n Phases Can Share Phase Angle
- Excellent DC and Transient Current Sharing
- Phase-Lockable Fixed Frequency 125kHz to 1MHz
- Supports Bidirectional Current Flow
- RSENSE or DCR Current Sensing
- Eliminates the Need to Route Sensitive Feedback and Control Signals
- 52-Lead (7mm × 8mm) QFN Package
