TIDA-00247, Single Chip 2-Wire Loop Powered, 4 to 20mA Current Loop RTD Temperature Transmitter

TIDA-00247, Single Chip 2-Wire Loop Powered, 4 to 20mA Current Loop RTD Temperature Transmitter. The conventional approach of using a high bridge excitation voltage and an operational amplifier to achieve a full-scale ADC input voltage increases chip count and overall power consumption. This solution utilizes the integrated ADC and operational amplifiers (OAs) of a microcontroller. In order to cut down the cost, the ADC/DAC use the main supply voltage as its reference voltage instead of including an external reference or selecting a more expensive ADC/DAC that features an internal reference. Leveraging the integrated peripherals of MCU enables low component count and low cost. This reference design is based on MSP430F2274 a mixed signal microcontroller