LTC3871
Bidirectional PolyPhase Synchronous Buck or Boost Controller
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Overview
Features and Benefits
- 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
Product Details
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 LTC3871 and LTC3871-1 have different current limit foldback characteristics.
Applications
- Automotive 48V/12V Dual Battery Systems
- Backup Power Systems
Product Lifecycle
Recommended for New Designs
This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.
Evaluation Kits (2)
Documentation & Resources
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R526 Reliability Data3/26/2018
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DC2348A - Demo Manual9/1/2016
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80V to 150V Non-Isolated DC/DC2/6/2018
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High Voltage Non-Isolated Devices1/5/2018
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How to Create a Dual-Output Voltage Rail with Source and Sink Functionality for ATE Applications1/16/2023 Analog Dialogue
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Bipolar, Bidirectional DC-to-DC Supply Sources and Sinks Current from 5 V to 24 V Input4/1/2020
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Sensor, Power Management, and Bus Solutions as Drivers of Global Megatrends2/1/2019 Thought Leadership
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48V/12V Dual Battery Automotive Systems Require Bi-Directional DC/DC Controllers for Optimum Performance10/12/2016
Tools & Simulations
LTspice
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.
Models for the following parts are available in LTspice:
LTC3871
LTpowerCAD
LTpowerCAD® is a power supply design program which selects power stage components, provides detailed power efficiency, shows quick loop Bode plot stability and load transient analysis, and can export to LTspice for simulation.
To open the project file for this circuit:
Step 1: Download and install LTpowerCAD on your computer.
Step 2: Click on the link(s) in the section below to download part-specific project files.
Step 3: If the project file doesn't run, right-click the link and select "Save Target As." Then start the LTpowerCAD tool and open the project file by selecing "Open Project" from the "File" menu.
Design tools for the following parts are available in LTpowerCAD:
LTC3871
LTC3871(BOOST)
Product Recommendations
LTC3871 Companion Parts
Design Resources
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.View our quality and reliability program and certifications for more information.
PCN-PDN Information
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Support & Discussions
LTC3871 Discussions
Sample & Buy
Ordering FAQs
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Buy Now Pricing
(**) Displayed Buy Now Price and Price Range is based on small quantity orders.
List Pricing
(*)The 1Ku list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.
Lead Times
Please see the latest communication from our CCO regarding lead times.
Sampling
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Evaluation Boards
Pricing displayed is based on 1-piece.
Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.