Abstract: A sensor system on an oscillator having variable loop gain level is described. Only when the oscillator loop gain is at least the level of one does the oscillator produce an AC output signal. The oscillator's ability to oscillate is controlled by the one or more sensor/transducer input signal levels which controls the Q level of an element in a resonate circuit which with other components forms a feedback network.

Abstract: A low power inductive proximity sensing system in which a DC voltage to the inductors is only applied for a short time period needed to detect the presence or absence of an appropriate object. After the detection time period is over, DC voltage is no longer applied to the inductors.

Abstract: A low power inductive proximity sensing system in which a DC voltage to the inductors is only applied for a short time period needed to detect the presence or absence of an appropriate object. After the detection time period is over, DC voltage is no longer applied to the inductors.

Abstract: Constant and accurate signal gain systems based on controlling signal amplifier gain level by applying the signal amplifier output signal to a signal level divider with a set ratio. The output signal of the signal level divider is applied to one input of the gain control amplifier, which is a differential amplifier, while the signal amplifier input signal is applied to the other input. The gain control amplifier output level is used to control the gain level of the signal amplifier. The gain control amplifier output level forces by negative feedback the gain control amplifier input levels to be substantially equal thus maintaining the signal amplifier gain level substantially constant.

Abstract: A system for providing voltage and current regulator sources based on a oscillator having variable loop gain is described. Only when the oscillator loop gain is at least the value of one does the oscillator oscillate. The oscillator's ability to oscillate is controlled by the one or more variable impedance or gain devices. Negative feedback of the voltage or current output level is used to control the loop gain of the oscillator circuit.

Abstract: Constant and accurate signal gain systems based on controlling signal amplifier gain level by applying the signal amplifier output signal to a signal level divider with a set ratio. The output signal of the signal level divider is applied to one input of the gain control amplifier, which is a differential amplifier, while the signal amplifier input signal is applied to the other input. The gain control amplifier output level is used to control the gain level of the signal amplifier. The gain control amplifier output level forces by negative feedback the gain control amplifier input levels to be substantially equal thus maintaining the signal amplifier gain level substantially constant.

Abstract: Voltage and current reference sources capable of providing an output signal level which is insensitive to temperature variations, radiation, and to variations in the input voltage supplied to the reference circuit. The reference output level is used to vary the temperature of at least one resistor that is in a resistor bridge network. By applying resistor temperature variation as negative feedback the voltage and current reference sources output voltage level is maintained at a relatively constant level.

Abstract: Constant and accurate signal gain systems based on controlling oscillator loop gain. A constant gain positive feedback network and an amplifier form an oscillator. Only when the oscillator loop gain is at least one does the oscillator produces an AC signal. Negative feedback of the oscillator's AC signal level is used to keep the loop gain close to or at the value of one by controlling the loop gain of the oscillator circuit. By maintaining the loop gain of the oscillator circuit substantially constant the signal gain is also maintained substantially constant.

Abstract: A current sensor system that uses a sensor resistor to sense current flow and in which the level of voltage drop across that resistor is used to control the current flow through another resistor, the input resistor, into a current integrator. The ratio of input resistor to sensor resistor resistance values determines the ratio of sense current to integrator input current level. By matching the temperature coefficients of the resistors the effects of temperature are reduced. The integrator output provides either directly or indirectly a voltage level, frequency, or duty cycle output signal to indicate the sensor resistor current level.

Abstract: A system for providing voltage and current regulator sources based on a oscillator having variable loop gain is described. Only when the oscillator loop gain is at least the value of one does the oscillator oscillate. The oscillator's ability to oscillate is controlled by the one or more variable impedance or gain devices. Negative feedback of the voltage or current output level is used to control the loop gain of the oscillator circuit.

Abstract: A method for comparing two signal with increased accuracy by using a reduced offset voltage comparator that has a offset zero mode and amplify mode. Additional comparators are used to indicate when the two signal are close in value. When the signal are close the reduced offset voltage comparator operation is changed from offset zero mode to amplify mode and the two signal are compared.

Abstract: A FET oscillator with increased frequency stability. This is accomplished by using a controlled voltage supply with error correction to power the amplifier stage of the oscillator. This voltage changes as the oscillator temperature increases in order to reduce the variation in frequency, caused by the amplifier and other frequency determining components changes. By using this compensated amplifier as the active section of an oscillator, the oscillator frequency stability is increased.

Abstract: A current sensor system that uses a sensor resistor to sense current flow and in which the level of voltage drop across that resistor is used to control the current flow through another resistor, the input resistor, into a current integrator. The ratio of input resistor to sensor resistor resistance values determines the ratio of sense current to integrator input current level. By matching the temperature coefficients of the resistors the effects of temperature are reduced. The integrator output provides either directly or indirectly a voltage level, frequency, or duty cycle output signal to indicate the sensor resistor current level.

Abstract: This invention relates to monostable and astable multivibrators in which the pulse width or frequency stability, respectively is increased by reducing the effect of the comparator input offset voltage. The reduction is accomplished by alternately reversing the input connections to the comparator.

Abstract: Constant and accurate signal gain systems based on controlling oscillator loop gain. A constant gain positive feedback network and an amplifier form an oscillator. Only when the oscillator loop gain is at least one does the oscillator produces an AC signal. Negative feedback of the oscillator's AC signal level is used to keep the loop gain close to or at the value of one by controlling the loop gain of the oscillator circuit. By maintaining the loop gain of the oscillator circuit substantially constant the signal gain is also maintained substantially constant.

Abstract: A system for comparing, measuring, or providing a reference signal based on a oscillator having variable loop gain is described. Only when the oscillator loop gain is at least the value of one does the oscillator produce an AC output signal. The oscillator's ability to oscillate is controlled by the one or more sensor/transducer input signal levels. In some cases, negative feedback of the AC output signal is also used to control the loop gain of the oscillator circuit keeping the loop gain at or close to the value of one. The system's output signal indicates whether the oscillator is oscillating or not, or the AC signal level required to just maintain oscillation.

Abstract: A system for comparing, measuring, or providing a reference signal based on a oscillator having variable loop gain is described. Only when the oscillator loop gain is at least the value of one does the oscillator produce an AC output signal. The oscillator's ability to oscillate is controlled by the one or more sensor/transducer input signal levels. In some cases, negative feedback of the AC output signal is also used to control the loop gain of the oscillator circuit keeping the loop gain at or close to the value of one. The system's output signal indicates whether the oscillator is oscillating or not, or the AC signal level required to just maintain oscillation.

Abstract: A FET oscillator with increased frequency stability. This is accomplished by using a controlled voltage supply with error correction to power the amplifier stage of the oscillator. This voltage changes as the oscillator temperature increases in order to reduce the variation in frequency, caused by the amplifier and other frequency determining components changes. By using this compensated amplifier as the active section of an oscillator, the oscillator frequency stability is increased.

Abstract: A method for comparing two signal with increased accuracy by using a reduced offset voltage comparator that has a offset zero mode and amplify mode. Additional comparators are used to indicate when the two signal are close in value. When the signal are close the reduced offset voltage comparator operation is changed from offset zero mode to amplify mode and the two signal are compared.

Abstract: This invention relates to monostable and astable multivibrators in which the pulse width or frequency stability, respectively is increased by reducing the effect of the comparator input offset voltage. The reduction is accomplished by alternately reversing the input connections to the comparator.