Abstract: A sensor apparatus and a method of operating the sensor apparatus can include one or more sensors and a circuit board, wherein the one or more sensors can include a rotatable component (e.g., pulse disk, crank, pin, shaft, etc), and an angular circuit board assembly that maintains the circuit board in an angular position with respect to the rotatable component in an arrangement that allows the rotatable component to dive through the circuit board. The sensor can be, for example, a magnetic sensor, a light emitting diode or a photo diode. The sensor apparatus can include a flow channel and the rotatable component can oscillate to provide a measurement of a flow of fluid through the flow channel. The sensor apparatus can be used for the mechanical/electrical detection of pulses of a rotary motion.

Abstract: A phototransistor apparatus and a method of operating the phototransistor apparatus. The phototransistor apparatus can include a phototransistor, a light source, and a supply voltage associated with the phototransistor. After switching on the supply voltage, the phototransistor can generate a phototransistor signal that is scanned, wherein the supply voltage associated with the phototransistor is switched on later than the light source, and wherein charge carriers in a base area of the phototransistor are reactive to a light pulse from the light source in a currentless state, and continue to react after the light source is switched off. Alternatively, the power supply of the phototransistor can be switched on before the light source is switched off. By delaying the switching on of the power supply of the phototransistor compared to the switching on of the light source, a significant current saving can be achieved.

Abstract: A sensor apparatus and a method of operating the sensor apparatus can include one or more sensors and a circuit board, wherein the one or more sensors can include a rotatable component (e.g., pulse disk, crank, pin, shaft, etc), and an angular circuit board assembly that maintains the circuit board in an angular position with respect to the rotatable component in an arrangement that allows the rotatable component to dive through the circuit board. The sensor can be, for example, a magnetic sensor, a light emitting diode or a photo diode. The sensor apparatus can include a flow channel and the rotatable component can oscillate to provide a measurement of a flow of fluid through the flow channel. The sensor apparatus can be used for the mechanical/electrical detection of pulses of a rotary motion.

Abstract: A phototransistor apparatus and a method of operating the phototransistor apparatus. The phototransistor apparatus can include a phototransistor, a light source, and a supply voltage associated with the phototransistor. After switching on the supply voltage, the phototransistor can generate a phototransistor signal that is scanned, wherein the supply voltage associated with the phototransistor is switched on later than the light source, and wherein charge carriers in a base area of the phototransistor are reactive to a light pulse from the light source in a currentless state, and continue to react after the light source is switched off. Alternatively, the power supply of the phototransistor can be switched on before the light source is switched off. By delaying the switching on of the power supply of the phototransistor compared to the switching on of the light source, a significant current saving can be achieved.

Abstract: A circuit that indicates a warning of low battery life so that an instrument supported by a battery, may have the battery replaced before the battery dies. A switch and series resistor may be connected between the battery and a capacitor. The switch may turn on when the voltage on the capacitor is below a first predetermined voltage limit, and the switch may be turned off when the voltage at the capacitor is above a second predetermined voltage limit. When the switch is on, a voltage on the resistor can be measured and current consumption can be calculated with measured voltage, resistor value and duty cycle of the switch. When the battery is discharged, its internal resistance and then its duty cycle may increase. When the duty cycle hits 100 percent, the battery may be nearly dead but with enough life for the circuit to issue the low battery warning.

Abstract: A circuit that indicates a warning of low battery life so that an instrument supported by a battery, may have the battery replaced before the battery dies. A switch and series resistor may be connected between the battery and a capacitor. The switch may turn on when the voltage on the capacitor is below a first predetermined voltage limit, and the switch may be turned off when the voltage at the capacitor is above a second predetermined voltage limit. When the switch is on, a voltage on the resistor can be measured and current consumption can be calculated with measured voltage, resistor value and duty cycle of the switch. When the battery is discharged, its internal resistance and then its duty cycle may increase. When the duty cycle hits 100 percent, the battery may be nearly dead but with enough life for the circuit to issue the low battery warning.