Circuit for converting a temperature dependent input signal to a temperature independent output signal

A bridge circuit, for use in conjunction with a variable resistor whose resistance varies predictably in response to a sensed parameter and which varies by a factor of K.sub.1 in response to a parasitic parameter, to generate an output signal which is independent of the parasitic parameter comprising:

• a voltage source connected to the variable resistor;
• a first resistance connected in series relationship with the variable resistor and said source operative to provide a first electrical circuit;
• a first voltage divider connected to said source in parallel with said first circuit, said first voltage divider having at least one fixed resistance connected in series with at least one variable resistance;
• said at least one variable resistance selected to be variable only in response to the parasitic parameters and arranged to provide a voltage at the junction of the at least one fixed resistance and the at least one variable resistance which varies by a factor of K.sub.2 in response to the parasitic parameter, K.sub.2 being inversely related to the voltage variation demonstrated at the junction of the variable resistor and said first resistance in the presence of the parasitic parameter;
• and
• second voltage divider means comprising second and third fixed resistances connected in series to form a signal terminal therebetween, said second fixed resistance also connected to the junction of the variable resistor with said first resistance and said third fixed resistance connected to the junction of said at least one variable resistance with the at least one fixed resistance.