3.1.2 Differential Output Sensor Interface

DAC provides a constant current of 100 μA for 2SMPP-02 differential output sensor excitation. OPA is configured as the gain stage, and the output of OPA provides the positive input channel of the differential ADCC.

The ADCC Differential mode interfaces with the sensor’s differential output signal. The ADCC also measures the excitation current of the sensor by measuring the voltage across a resistor connected between the sensor pin ICC and circuit ground. This way, implementing a feedback loop can maintain a 100 μA constant current. Adjusting the DAC output value can modify the current.

FVR provides stable voltage reference to the ADCC and DAC modules. Ambient pressure value is displayed on the terminal window when using a UART peripheral after processing the ADC result.

Refer to the code example above for implementation details using the PIC16F17146 microcontroller and the Getting Started with Integrated Analog Peripherals of PIC® Microcontroller technical brief.

Application examples using the ADC in Single-Ended Measurement mode are featured in the following sections.