Patent ID: 7305881

Claim:
A thermal accelerometer, comprising: a thermal acceleration sensor including a substrate, at least one cavity formed in the substrate, a fluid disposed in the cavity, at least one heater element suspended over the cavity, a plurality of temperature sensing elements disposed substantially in a plane of the substrate and at substantially equal distances from the heater element, wherein the plurality of temperature sensing elements is operative to detect a temperature of the fluid generated in response to an applied acceleration, and to provide a signal representing the detected fluid temperature; and signal conditioning circuitry operative to receive the signal representing the detected fluid temperature, to implement a temperature dependent function, and to process the received signal using the temperature dependent function for generating an output signal indicative of the applied acceleration, whereby the signal conditioning circuitry provides a compensation for sensitivity variations of the sensor over a predetermined range of temperature, the signal conditioning circuitry including: a first reference voltage generator including at least one sensor operative to detect an ambient temperature, the first reference voltage generator being operative to provide a first reference voltage level proportional to the ambient temperature; at least one analog-to-digital (A-to-D) converter operative to receive the signal representing the detected fluid temperature, to convert the received signal to digital form, and to provide a digital signal inversely proportional to the first reference voltage level; and at least one digital-to-analog (D-to-A) converter operative to receive the digital signal provided by the A-to-D converter, to convert the digital signal to analog form, and to provide an analog signal directly proportional to the first reference voltage level, the analog signal corresponding to the output signal indicative of the applied acceleration.