| CPC G01K 7/25 (2013.01) [H03F 3/45071 (2013.01); H03M 1/12 (2013.01)] | 18 Claims |
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1. A circuit comprising:
a variable resistor coupled in series with a selected non-linear temperature coefficient (NTC) element;
an operational amplifier having a non-inverting input to which an input voltage is applied, an inverting input coupled to the variable resistor, and an output at which an amplifier output signal indicative of a temperature sensed by the NTC element is generated, the amplifier output signal being a linearized version of the non-linear resistance of the NTC element; and
a feedback resistor coupled between the output of the operational amplifier and the inverting input of the operational amplifier,
wherein the variable resistor and feedback resistor are formed from a resistor network, the resistor network comprising
a plurality of resistive elements coupled in series, with a first adjacent pair of the resistive elements interconnected at a switch junction and a second adjacent pair of the resistive elements interconnected at a transmission gate junction;
a switch having a first terminal coupled to the switch junction, a second terminal coupled to the inverting input of the operational amplifier, and a control terminal that receives a control signal configuring a resistance of the variable resistor; and
a transmission gate coupled between the output of the operational amplifier and the transmission gate junction, the transmission gate comprising a control terminal that receives a control signal configuring a resistance of the feedback resistor,
wherein the resistance of the variable resistor and the resistance of the feedback resistor are configured based on a specification of the NTC element.
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