Linearized temperature sensor

Abstract

A temperature sensor corrects the parabolic curvature error in the output signal without attempting to linearize the reference voltage itself. A temperature sensor produces a temperature output signal that is a function of the ratio of a temperature dependent voltage to a reference voltage. The temperature sensor uses a nonlinear reference voltage, e.g., the reference voltage conforms to a curve with an approximately hyperbolic shape over a temperature range, so that the ratio of the temperature dependent voltage to the hyperbolic reference voltage will be linear. The hyperbolic reference voltage is generated by summing a reference voltage with an appropriate temperature dependent voltage. The “gain” or slope of the ratio is altered by adjusting a scaling factor. Finally, the offset of the ratio is adjusted so that the temperature sensor produces the appropriate output signal at ambient temperature. Thus, despite the present of curvature in the reference voltage of the temperature sensor, a highly linear and accurate temperature sensor may be constructed using the hyperbolic linearization technique without requiring complex or expensive reference voltage correction circuits.

Dependencies are inferred from the claim text.