Method and means for converting an analog signal into a digital signal

In a circuit for converting an analog input voltage signal (preferably in the form of a low-frequency rectangular voltage) to a digital output signal proportional to the input voltage, in which the input voltage is integrated to an integrator voltage over a predetermined integration time and, after the expiration of the predetermined integration time, the integrator voltage is de-integrated to zero over a de-integration time by a reference voltage and the input voltage is found from the ratio of the de-integration time to the integration time, multiplied by the reference voltage, the improvement comprising means for producing modulation pulses from the reference voltage and means for superimposing the modulation pulses on the input voltage during the integration time so as to influence the integrator voltage in such a way that even at different input voltages, substantially equal modulation of the integrator is achieved.

In a method for converting an analog input voltage signal (preferably in the form of a low-frequency rectangular voltage) to a digital output signal proportional to the input voltage, in which the input voltage is integrated to an integrator voltage over a given integration time and, after the expiration of the integration time, the integrator voltage is de-integrated to zero over a de-integration time by a reference voltage and the input voltage is found from the ratio of the de-integration time to the integration time, multiplied by the reference voltage, the additional steps of superimposing modulation pulses, preferably derived from the reference voltage, on the input voltage during the integration time, thereby influencing the integration voltage so that even at different input voltages, substantially equal modulation of the integrator is achieved, controlling the number and/or the polarity and/or the pulse width of the modulation pulses, and controlling in the mth conversion, m being a positive integer, the number and/or the polarity and/or the pulse width of the modulation pulses as a correlation of what magnitude integrator voltage was achieved in the m-1th conversion.

In a method for converting an analog input voltage signal (preferably in the form of a low-frequency rectangular voltage) to a digital output signal proportional to the input voltage, in which the input voltage is integrated to an integrator voltage over a given integration time and, after the expiration of the integration time, the integrator voltage is de-integrated to zero over a de-integration time by a reference voltage and the input voltage is found from the ratio of the de-integration time to the integration time, multiplied by the reference voltage, the additional step of superimposing modulation pulses, preferably derived from the reference voltage, on the input voltage during the integration time, thereby influencing the integrator voltage so that even at different input voltages, substantially equal modulation of the integrator is achieved, measuring the integrator voltage constantly over the integration time, and then, if the integrator voltage deviates from selected default values during the integration time, influencing the modulation pulses so that a given voltage area is produced.

In a circuit for converting an analog input voltage signal (preferably in the form of a low-frequency rectangular voltage) to a digital output signal proportional to the input voltage, in which the input voltage is integrated to an integrator voltage over a given integration time and, after the expiration of the integration time, the integrator voltage is de-integrated to zero over a de-integration time by a reference voltage and the input voltage is found from the ratio of the de-integration time to the integration time, multiplied by the reference voltage, the improvement comprising means for producing modulation pulses from the reference voltage, means for superimposing the modulation pulses on the input voltage during the integration time, thereby influencing the integrator voltage so that even at different input voltages, substantially equal modulation of the integrator is achieved, and means for controlling in the mth conversion, m being a positive integer, the number and/or the polarity and/or the pulse width of the modulation pulses as a correlation of what magnitude integrator voltage was achieved in the m-1th conversion.

In a circuit for converting an analog input voltage signal (preferably in the form of a low-frequency rectangular voltage) to a digital output signal proportional to the input voltage, in which the input voltage is integrated to an integrator voltage over a given integration time and after the expiration of the integration time, the integrator voltage is de-integrated to zero over a de-integration time by a reference voltage and the input voltage is found from the ratio of the de-integration time to the integration time, multiplied by the reference voltage, the improvement comprising means for producing modulation pulses from the reference voltage, means for superimposing the modulation pulses on the input voltage during the integration time, thereby influencing the integrator voltage so that even at different input voltages, substantially equal modulation of the integrator is achieved, means for measuring the integrator voltage constantly over the integration time, and means for influencing the modulation pulses so that a given voltage area is produced if the integrator voltage deviates from selected default values during the integration time.