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- 3-Wire RTD Measurement System, -200°C to 850°C (TIPD120 Verified Design) (Rev. A)
(PDF 1419 KB)
02 Jul 2014 1,300 views
TIPD120 Design File
(ZIP 9891 KB)
11 Nov 2013 148 views
This TI Precision Verified Design provides the theory, component selection, simulation, complete PCB schematic & layout, bill of materials, and measured performance of a single-supply, 3-wire RTD acquisition system that accurately measures temperature from -200°C - 850°C. The voltage input and reference voltage are placed in a ratiometric configuration in order to reduce the errors from noise and drift and improve overall system accuracy. The ADS1247 simplifies the front-end solution by incoorporating the required current sources, programmable gain amplifier, and digitally-controlled multiplexer onto one chip. A "chopping" technique is used to minimize the effects of mismatch between the two current sources. The TPS7A4901 adjustable-output, high-PSRR LDO is suggested as a cleaner power alternative over the existing USB supply to further improve system accuracy.
- TI Precision Designs: Verified Design
- Contains Theory, component selection, simulation, complete PCB schematic & layout, bill of materials, and measured performance
- -200°C - 850°C, 3-wire RTD ratiometric measurement
- Single, 5V Supply Solution
- Utilizes ADS1247, 24-bit ΔΣ ADC
- Utilizes TPS7A4901 ultra-low noise LDO for precision measurements