1. Products
  2. Power Management
  3. Switching Regulators
  4. Buck-Boost Regulators
  5. External Power Switch Buck-Boost Controllers
  6. LT8708


Overview

Features and Benefits

  • Single Inductor Allows VIN Above, Below, or Equal to VOUT
  • Six Independent Forms of Regulation
    • VIN Current (Forward and Reverse)
    • VOUT Current (Forward and Reverse)
    • VIN and VOUT Voltage
  • Forward and Reverse Discontinuous Conduction Mode Supported
  • Supports MODE and DIR Pin Changes While Switching
  • VINCHIP Range 2.8V (Need EXTVCC > 6.4V) to 80V
  • VOUT Range: 1.3V to 80V
  • Synchronous Rectification: Up to 99% Efficiency
  • Available in 40-Lead (5mm × 8mm) QFN with High Voltage Pin Spacing and 64-Lead (10mm × 10mm) eLQFP
  • AEC-Q100 Qualified for Automotive Applications

Product Details

The LT8708 is a high performance buck-boost switching regulator controller that operates from an input voltage that can be above, below or equal to the output voltage. Features are included to simplify bidirectional power conversion in battery/capacitor backup systems and other applications that may need regulation of VOUT, VIN, IOUT, and/or IIN. Forward and reverse current can be monitored and limited for the input and output sides of the converter. All four current limits (forward input, reverse input, forward output and reverse output) can be set independently using four resistors on the PCB.

The MODE pin can select between discontinuous conduction mode (DCM), continuous conduction mode (CCM), hybrid conduction mode (HCM) and Burst Mode® operation. In combination with the DIR (direction) pin, the chip can be configured to process power only from VIN to VOUT or only from VOUT to VIN. With a wide 2.8V to 80V input and 1.3V to 80V output range, the LT8708 is compatible with most solar, automotive, telecom and battery-powered systems.

APPLICATIONS

  • High Voltage Buck-Boost Converters
  • Bidirectional Charging System
  • Automotive 48V Systems

Product Lifecycle icon-recommended 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)

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.

LTspice

Models for the following parts are available in LTspice:

LT8708
LT8708-1

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.

Part Number Material Declaration Reliability Data Pin/Package Drawing CAD Symbols, Footprints & 3D Models
LT8708ELWE#PBF Material Declaration Reliability Data 64-Lead LQFP (10mm x 10mm w/ EP)
LT8708ELWE#WPBF Material Declaration Reliability Data 64-Lead LQFP (10mm x 10mm w/ EP)
LT8708EUHG#PBF Material Declaration Reliability Data 40-Lead QFN (5mm x 8mm x 0.75mm w/ EP)
LT8708EUHG#TRPBF Material Declaration Reliability Data 40-Lead QFN (5mm x 8mm x 0.75mm w/ EP)
LT8708HLWE#PBF Material Declaration Reliability Data 64-Lead LQFP (10mm x 10mm w/ EP)
LT8708HLWE#WPBF Material Declaration Reliability Data 64-Lead LQFP (10mm x 10mm w/ EP)
LT8708HUHG#PBF Material Declaration Reliability Data 40-Lead QFN (5mm x 8mm x 0.75mm w/ EP)
LT8708HUHG#TRPBF Material Declaration Reliability Data 40-Lead QFN (5mm x 8mm x 0.75mm w/ EP)
LT8708ILWE#PBF Material Declaration Reliability Data 64-Lead LQFP (10mm x 10mm w/ EP)
LT8708ILWE#WPBF Material Declaration Reliability Data 64-Lead LQFP (10mm x 10mm w/ EP)
LT8708IUHG#PBF Material Declaration Reliability Data 40-Lead QFN (5mm x 8mm x 0.75mm w/ EP)
LT8708IUHG#TRPBF Material Declaration Reliability Data 40-Lead QFN (5mm x 8mm x 0.75mm w/ EP)
Wafer Fabrication Data

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Sample & Buy


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Evaluation Boards

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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.