Motorola Corporation

Timothy T Rueger

William J Roeckner

Walter S Czarnocki

Neal W Hollenbeck

Lawrence F Connell

An electronically calibrated sensor (100) includes a sensing element (102) with an output coupled to a signal conditioning circuit (104). The signal conditioning circuit (104) is adapted to be highly computationally efficient and operable for compensating for temperature and part-to-part variation on the sensing element output for providing a useable sensor output signal. The signal conditioning circuit (104) includes an analog-to-digital/digital-to-analog (ADC/DAC) conversion device (112). The ADC/DAC (112) is operable to perform both analog input signal analog-to-digital conversion and digital output signal digital-to-analog conversion. The ADC/DAC (112) is further adapted to provide analog control signals to input signal conditioning circuits (104, 106).

Signal conditioning circuit including a combined ADC/DAC, sensor system,

A polynomial calculator device is applied to calibrate a sensing device. Preferably the sensing device (100) includes a sensing element (102) with an output coupled to a signal conditioning circuit (104). The signal conditioning circuit (104) is adapted to be highly computationally efficient and operable for compensating for temperature and part-to-part variation on the sensing element output for providing a useable sensor output signal. A calibration method relies on a unique polynomial calculator (118) that is implemented as part of the signal conditioning circuit (104). The sensor is preferably manufactured and packaged prior to calibration so as to avoid any post-calibration processing error. The packaged sensor is calibrated and a number of calibration values are retained in a memory (114) and accessed by the calibration method during sensing element signal processing.

Polynomial calculator device, and method therefor

An electronic device (10) includes a signal processor (14) receiving an input signal requiring calibration, a data storage device (38) providing calibration data to the signal processor (14), a calibration controller (32) allowing the calibration data to be written to the data storage device (38) across at least an output terminal (22), and such that the signal processor (14) produces a calibrated output signal via an output driver (30) to the output terminal (22).

Device and method for calibrating a signal

A circuit and method provides a low distortion buffer by using a resistive divider stage (18, 20) and a gain stage (12) whose gain is equal to the inverse of the attenuation ratio of the resistive divider to provide unity gain. Multiple inputs (14, 42, 44, . . . 46) to the buffer circuit are accommodated by an input switching network (30, 38). The gain error introduced by the resistance of the switching network (30, 38) is canceled by placing an equivalent network (60) in a feedback path of the gain stage. The preferred circuit topology is well-suited to low-voltage applications and provides a low-distortion output. Circuits for reducing power consumption (68, 70) and minimizing undesirable transients (72) are also provided.

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Rolling Meadows, IL, United States of America

Timothy T Rueger