Description

This TI Precision Verified Design implements a hardware compensated 3-wire RTD acquisition system that accurately measures temperature from  0 °C - 100 °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 through integration of the required current sources: programmable gain amplifier: and digitally-controlled multiplexer in to one chip. The current sources are chopped to minimize any mismatch between the two sources. The TPS7A4901 adjustable-output: high-PSRR LDO is suggested as a clean power alternative versus the existing USB supply to further improve system accuracy.