Methods and related systems of a readout circuit for use with a wheatstone bridge sensor

A method comprising:

• driving a first electrical current to a first port of a Wheatstone bridge sensor, and electrically floating a second port of the Wheatstone bridge sensor, first port defined between a first set of sensor elements of the Wheatstone bridge sensor and the second port defined between a second set of sensor elements of the Wheatstone bridge sensor;
• measuring response of the first set of sensor elements, the measuring response of the first set of sensor elements creates a first measurement;
• and then
• driving a second electrical current to the second port of the Wheatstone bridge sensor, and electrically floating the first port of the Wheatstone bridge sensor;
• and
• measuring response of the second set of sensor elements, the measuring response of the second set of sensor elements creates a second measurement.

A method comprising:

• driving a first excitation signal to a first port defined between a first set of sensor elements of a Wheatstone bridge sensor, and refraining from driving the first excitation signal to a second port defined between a second set of sensor elements of the Wheatstone bridge sensor;
• measuring response to the first set of sensor elements to create a first measurement by applying a balancing current to a third port and a fourth port of the Wheatstone bridge sensor, the applying by way of a digital-to-analog (D/A) converter such that a voltage across the third port and the fourth port is substantially zero, the first measurement based on the balancing current;
• and then
• driving a second excitation signal to the second port of the Wheatstone bridge sensor and refraining from driving the second excitation signal to the first port;
• measuring response of the second set of sensor elements to create a second measurement;
• and
• creating a digital representation of the first measurement by:
• reading, by an analog-to-digital (A/D) converter, an output signal from a differential amplifier electrically coupled to the third and fourth ports of the Wheatstone bridge sensor, the reading creates a digital value;
• supplying the digital value to the D/A converter;
• and
• creating the digital representation by averaging the digital value over a predetermined amount of time.

A sensor circuit comprising:

• a first, second, third, and fourth sensor connections, the first, second, third, and fourth sensor connections configured to couple to a first, second, third, and fourth ports of a Wheatstone bridge sensor;
• a switch network coupled to the third and fourth sensor connections, in a first mode the switch network couples a first current source to the third sensor connection and electrically floats the fourth sensor connection, and in a second mode couples a second current source to the fourth sensor connection and electrically floats the third sensor connection;
• a differential amplifier that defines a first differential input, a second differential input, and a differential output, the first and second sensor connections electrically coupled to the first and second differential inputs, respectively;
• an analog-to-digital (A/D) converter that defines an analog input and a digital output, the analog input electrically coupled to the differential output of the differential amplifier;
• a digital-to-analog (D/A) converter that defines a digital input and an analog output, the digital input electrically coupled to the digital output of the A/D converter, and the analog output coupled to the first and second sensor connections;
• a decimator coupled to the digital output of the A/D converter, the decimator configured to create measurement values based on values read from the digital output of the A/D converter;
• and
• wherein, in the first mode the sensor circuit is configured to make a first measurement of a first set of sensors in the Wheatstone bridge sensor, and in the second mode the sensor circuit is configured to make a second measurement of a second set of sensors in the Wheatstone bridge sensor.