Back to results
US 5,795,069 AGranted
Temperature sensor and method
AssigneeSSI Technologies, Inc.
InventorsMichael F. Mattes, James D. Seefeldt, Paul B. Rozgo
Life of this patent
Estimating the term…
Abstract
A temperature sensor using doped polysilicon resistors in a bridge configuration, an amplifier, and a doped polysilicon feedback resistor between the input and the output of the amplifier. The polysilicon resistors are doped with selected concentrations of impurities such as boron, phosphorus, arsenic or antimony. The resistors are doped to establish predetermined temperature coefficients so that the resistors exhibit a predetermined temperature dependence. This temperature dependence is utilized to create a temperature sensor that is stable, accurate, and rugged and that has a generally linear output to temperature response.
Claims28
A temperature sensor comprising:
- a bridge having a first arm including a first and a second doped polysilicon resistor and a first node between said first and second resistor, and a second arm including a third and a fourth doped polysilicon resistor and a second node between said third and fourth resistors, wherein said resistors generate a differential voltage at said first and second nodes that is functionally related to ambient temperature;
- an amplifier in communication with said bridge having as an input said differential voltage, said amplifier having a gain that is adjustable in response to variations in ambient temperature, and said amplifier having an electrical signal output that is related to the ambient temperature;
- and
- a doped polysilicon feedback resistor connected between said input and said output of said amplifier, said feedback resistor having a predetermined temperature coefficient such that as the ambient temperature varies, the resistance of said feedback resistor varies to automatically adjust said gain of said amplifier.
1 more element
A method of measuring ambient temperature, said method of comprising the steps:
- (a) providing an amplifier having a predetermined gain at a predetermined reference temperature;
- (b) generating a differential signal functionally related to ambient temperature using a bridge comprised of a first arm including a first and a second doped polysilicon resistor and a first node between the first and second resistor, and a second arm including a third and a fourth doped polysilicon resistor and a second node between the third and fourth resistors, wherein the resistors generate the differential signal at the first and second nodes;
- (c) amplifying the differential signal using the amplifier;
- and
- (d) adjusting the gain of the amplifier in response to changes in ambient temperature using a doped polysilicon feedback resistor connected between the input and the output of the amplifier, the feedback resistor having a predetermined temperature coefficient such that as the ambient temperature varies, the resistance of the feedback resistor varies to automatically adjust the gain of the amplifier so as to produce an electrical output indicative of the ambient temperature.
2 more elements
A temperature sensor comprising:
- an integrated circuit component including a full-bridge doped polysilicon resistor network having a first arm for generating a first reference voltage and having a second arm for generating a second reference voltage, said first arm including a first and a second doped polysilicon resistor, said second arm including a third and a fourth doped polysilicon resistor, said resistors being doped with an impurity so as to have predetermined temperature coefficients such that the impedance of said component varies in accordance with changes in ambient temperature;
- and
- an amplifier for generating an electrical output functionally related to the impedance of said component, said amplifier having an input, an output, and a gain, said gain varying in accordance with changes in ambient temperature.
A temperature sensor comprising:
- a temperature sensing element, said temperature sensing element including first and second doped polysilicon resistors having different temperature coefficients, wherein said temperature sensing element produces a first voltage that varies with changes in ambient temperature;
- a resistor network, said resistor network including third and fourth doped polysilicon resistors having the same temperature coefficients;
- an amplifier having an input, an output and a feedback gain, said feedback gain being unaffected by changes in ambient temperature;
- and
- a feedback resistor connected between said input and said output of said amplifier, said feedback resistor being a doped polysilicon resistor.
2 more elements
A temperature sensor comprising:
- a bridge comprised of a first arm including a first and a second doped polysilicon resistor and a first node between said first and second resistor, and a second arm including a third and a fourth doped polysilicon resistor and a second node between said third and fourth resistors, wherein said first and second resistors generate a first voltage at said first node that is functionally related to ambient temperature, wherein said third and fourth resistors generate an offset voltage that is non-functionally related to temperature;
- an amplifier in communication with said bridge, said amplifier having as an input said first voltage and said offset voltage, having an output that is related to the ambient temperature and having a feedback gain;
- and
- a doped polysilicon feedback resistor connected between said input and said output of said amplifier.
1 more element
Dependencies are inferred from the claim text.