An application note on how to implement an embedded system circuit with single-supply operational amplifiers.
Operational amplifiers are considered one of the building blocks of electronic circuits. In this note, the author describes the basic op-amp circuits with single-supply. But what we are more interested is the design of a single-supply op-amp circuit for temperature measurement.
An example of such circuit is shown below:
In this circuit, a PT100 is used to measure temperature. Such sensor needs current excitation, thus a current-source op-amp configuration is used. Moreover, gain and anti-aliasing circuits are also provided. The conditioned sensor signal is fed to a 12-bit ADC and then read by an 8-bit microcontroller.