Automotive High-Voltage Interlock Reference Design


Design files


This reference design is a low BOM design that has good coverage of automotive interlock connection diagnosis. In hybrid or electric vehicles (HEV/EVs), battery management systems, traction inverters, DCDC converters, onboard chargers, and other subsystems that operate at high voltages need to have interlock. Interlock is a current and voltage loop mechanism used to detect tampering or opening of the high-voltage equipment or service disconnect switch.This design covers generating and monitoring mechanism of high voltage interlock system.

  • Unidirectional interlock system
  • Tristate operation with unidirectional system
  • Wide coverage of interlock loop fault diagnosis
  • >97% accurate low-side current sense at >5mA
  • Protection for automotive output line faults
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A fully assembled board has been developed for testing and performance validation only, and is not available for sale.

Design files & products

Design files

Download ready-to-use system files to speed your design process.

TIDUD43A.PDF (3887 K)

Reference design overview and verified performance test data


Detailed schematic diagram for design layout and components


Complete listing of design components, reference designators, and manufacturers/part numbers


Detailed overview of design layout for component placement


Files used for 3D models or 2D drawings of IC components


Design file that contains information on physical board layer of design PCB


PCB layer plot file used for generating PCB design layout


Includes TI products in the design and potential alternatives.

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Technical documentation

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* Design guide Automotive High-Voltage Interlock Monitoring Reference Design (Rev. A) Apr. 16, 2018

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