Patent ID: 8337082

Claim:
A tunable temperature measurement circuit comprising: a source node maintained at a predetermined source voltage; a ground node maintained at a predetermined ground voltage; a bridge circuit comprising: a first resistance temperature detector connected between the source node and a first measurement node, a first reference resistor connected between the first measurement node and the ground node, a potentiometer connected between the source node and a reference node, and a scaling resistor connected between the reference node and the ground node; a first programmable gain instrumentation amplifier wherein a first input to the first programmable gain instrumentation amplifier is connected to the reference node, a second input to the first programmable gain instrumentation amplifier is connected to the first measurement node, and the output of the first programmable gain instrumentation amplifier is representative of the temperature sensed by the first resistance temperature detector; and, further comprising a bypass circuit connected between the first measurement node and the ground node, wherein the bypass circuit comprises a bypass switch in series with a bypass resistor and wherein the bypass circuit pulse width modulates a current passing through the first resistance temperature detector.