The LTC3871/LTC3871-1 is a high performance bidirectional buck or boost switching regulator controller that operates in either buck or boost mode on demand. It regulates in buck mode from VHIGH-to-VLOW and boost mode from VLOW-to-VHIGH depending on a control signal, making it ideal for 48V/12V automotive dual battery systems. An accurate current programming loop regulates the maximum current that can be delivered in either direction. The LTC3871/LTC3871-1 allows both batteries to supply energy to the load simultaneously by converting energy from one battery to the other.
Its proprietary constant-frequency current mode architecture enhances the signal-to-noise ratio enabling low noise operation and provides excellent current matching between phases. Additional features include discontinuous or continuous mode of operation, OV/UV monitors, independent loop compensation for buck and boost operation, accurate output current monitoring and overcurrent protection. The LTC3871ILXE and LTC3871-1 have different current limit foldback characteristics.
Feature
- Unique Architecture Allows Dynamic Regulation of Input Voltage, Output Voltage or Current
- VHIGH Voltages Up to 100V
- VLOW Voltages Up to 30V
- Synchronous Rectification: Up to 97% Efficiency
- ADI-Proprietary Advanced Current Mode Control
- ±1% Voltage Regulation Accuracy Over Temperature
- Accurate, Programmable Output Current Monitoring and Regulation for Both Buck and Boost Operation
- Selectable Buck and Boost Current Sense Limits
- Programmable DRVCC/EXTVCC Optimizes Efficiency
- Programmable VHIGH UV and OV Thresholds
- Programmable VLOW OV Threshold
- Phase-Lockable Frequency: 60kHz to 460kHz
- Multiphase/Multi-ICs Operation Up to 12 Phases
- Selectable CCM/DCM Modes
- Thermally Enhanced 48-Lead LQFP Package
Applications
- Automotive 48V/12V Dual Battery Systems
- Backup Power Systems