Leakage Current Measurement Reference Design for Determining Insulation Resistance


Design files


This reference design measures insulation resistance up to 100 MΩ. It has an on-board isolated 500-Vdc power supply and an isolated signal conditioning circuit to measure the leakage current. This design is useful to find leakage due to insulation breakdown in transformer and motor windings.

  • Leakage current measurement circuit with option for programmable current sense amplifier and switchable shunt resistors
  • Range of measurement: 0 to 100 MΩ with accuracy of 5% (un-calibrated)
  • Test voltage level derived from IEEE 43-2000 (recommended practice for testing insulation resistance of rotating machinery)
  • On-board isolated 500-V power supply to measure insulation resistance
  • Provision for calibration resistor on board
  • Hardware support for start-of-frame detect allows implement IEEE1588 PTP
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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.

TIDU873A.PDF (2507 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

TIDRDQ6.ZIP (6588 K)

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

TIDCA04.ZIP (897 K)

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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Type Title Date
* Design guide Leakage Current Measurement for Determining Insulation Resistance Design Guide (Rev. A) Apr. 30, 2015
Selection guide Current Sense Amplifiers (Rev. E) Sep. 20, 2021
Technical article How to detect insulation failures in electrical equipment – part 2 PDF | HTML May 02, 2016

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