| 摘要 |
PURPOSE:To accurately transmit an analog signal and to lessen the influence of the change of temperature, etc., by dividing the transmission quantity of a measurement value by the transmission quantity of a reference value through the use of one of plural photocouplers for the transmission of the reference value and the others for the transmission of the measurement value. CONSTITUTION:The unsaturation range of the light emitting strength of the photocoupler 4 is used for a current value flowing through a light emitting diode 5. As the photocoupler 4 is a current transmission element, a current flowing through the light emitting diode 5 proportionally flows between the emitter and collectors of a phototransistor 6. Thus the current flowing through the phototransistor 6 is converted by the resistances 7, 8 and is outputted as a voltage value. An input value of which disturbance factors such as the change of temperature, aging deterioration, etc., are made minimum can be obtained by dividing the voltage value of dividend transmitted and converted by respective channels for transmitting the signal by the voltage value of a divisor transmitted and converted by a channel for the reference voltage through the use of an analog divider 10. |
