Methods and systems for temperature compensation of physical property sensors

A temperature compensation method for a physical property sensor, said method comprising the steps of:

• locating a bridge circuit on a physical property sensor substrate wherein said bridge circuit comprises a plurality of components, including at least one heating element and a plurality of resistors, including a plurality of compensating resistors, wherein said plurality of compensating resistors includes first and second temperature independent resistors;
• simultaneously driving an imbalance of said bridge circuit to a zero value and a supply voltage thereof to a level required to stabilize said heating element at a required temperature rise above an ambient temperature, wherein said heating element comprises a thin-film heating material;
• dynamically compensating for a temperature coefficient of resistance of said thin-film heating material and a temperature dependence of said plurality of of resistors and said heating element(s) of said bridge circuit components and a temperature dependence of a physical property thereof, utilizing said compensating resistors of said bridge circuit, wherein said physical property includes at least one of the following:
• thermal conductivity, specific heat, compressibility, octane number, heating value, speed of sound, and viscosity;
• increasing a resistance value of said first temperature independent resistor to compensate for a temperature dependence of a physical property value, wherein said physical property value comprises a value of at least one of the following:
• thermal conductivity, specific heat, compressibility, octane number, heating value, speed of sound, and viscosity;
• adjusting the resistance value of said second temperature independent resistor such that, for said increased resistance value of said first temperature independent resistor, said heating element is maintained at said required temperature rise above said ambient temperature;
• minimizing a change in a bridge voltage or said bridge circuit as said ambient temperature is varied over a required range by an optimal choice of a value of said first temperature independent resistor;
• and
• selecting said bridge voltage as a supply voltage generated by an amplification or a bridge circuit imbalance, such that said bridge voltage serves as a sensor output signal of said physical property sensor.

A temperature compensation system for a physical property sensor, comprising:

• a bridge circuit comprising a plurality of components, including at least one heating element comprising a thin-film heating material and a plurality of resistors, including a plurality of compensating resistors, wherein said plurality of compensating resistors includes a temperature independent resistor, the resistance value of said temperature independent resistor being adjusted to compensate for a temperature coefficient of resistance of said at least one heating element;
• a physical property sensor substrate wherein said bridge circuit is located on said physical property sensor substrate and wherein an imbalance of said bridge circuit is driven to a zero value while a supply voltage thereof is simultaneously driven to a level required to stabilize said heating element at a required temperature rise above an ambient temperature;
• and
• a compensator for dynamically compensating for at a temperature coefficient of resistance of said thin-film heating material and a temperature dependence of said plurality of said resistors and said heating element(s) of said bridge circuit components and a temperature dependence of a physical property thereof, wherein said compensator comprises said plurality of compensating resistors of said bridge circuit.