Analog Linearized 3-Wire PT1000 RTD to 2-Wire 4-20mA Current Loop Transmitter Reference Design


Design files


This design features a single-chip solution to linearize and transmit a 3-wire PT1000 RTD over the industry standard 2-wire 4-20mA current loop.  The design was configured for a -50°C to 250°C  temperature range, but other temperature ranges can be achieved by adjusting the component values as discussed in the Theory of Operation section of the reference design guide.  Unadjusted design accuracy was measured to be less than 0.15°C over the selected RTD temperature span.

  • Input:  3-Wire PT1000 RTD
  • RTD Temperature Range:  -50°C to 250°C
  • Output:  2-Wire 4-20mA Current Loop
  • Includes analog RTD sensor linearization for >40x linearity improvement over end-point fit
  • Reference design includes theory, calculated error analysis, component selection, PCB layout, and measured results
??image.gallery.download_en_US?? View video with transcript Video

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.

TIDUB11.PDF (997 K)

Reference design overview and verified performance test data

TIDCBH5.ZIP (1130 K)

Detailed schematic diagram for design layout and components

TIDRJ17.PDF (210 K)

Detailed schematic diagram for design layout and components

TIDRJ18A.PDF (300 K)

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


Includes TI products in the design and potential alternatives.

4-20mA signal conditioners

XTR1124-20-mA current transmitters with sensor excitation (2 x 250-µA) and linearization

Data sheet: PDF

Technical documentation

= Top documentation selected by TI
No results found. Please clear your search and try again.
View all 1
Type Title Date
* Design guide Analog 3-Wire PT1000 RTD to 2-Wire 4-20mA Current Loop Transmitter Design Guide Nov. 09, 2015

Support & training

TI E2E™ forums with technical support from TI engineers

View all forum topics

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​