MULTI-INPUT CIRCUIT

摘要

Disclosed is a multi-input circuit comprising: a first terminal allowing the input of a sensor signal from a current means, an RTD temperature sensor and a TC temperature sensor; a second terminal allowing the input of a compensated signal from the RTD temperature sensor and a sensor signal from a voltage means; a grounded third terminal, which is grounded, allowing a common signal input from the current means, RTD temperature sensor, TC temperature sensor and voltage means; a current means sensor signal detection unit which is connected between the first terminal and the third terminal; a multiplexor in which the first to third terminals and an output terminal of the current means sensor signal detection unit are each connected in input ports; a key input unit for selecting an input port for receiving the sensor signal from the multiplexor; a power source unit for supplying power for sensing a change in the resistance value in the RTD temperature sensor; a switch for turning the power source on or off, the power source being supplied from the power source unit to the RTD temperature sensor; and a control unit for outputting, on the basis of the selection of the key input unit, a control signal for selecting the input port of the multiplexor and a control signal for controlling the on/off state of the switch, and subsequently receiving the sensor signal which is input into the input port of the multiplexor. Temperature sensor signals, analog voltage signals, and analog current signals from control measurement devices, such as a thermostat and panel meter, are received from a single input terminal, and the signal types are differentiated via a diode, thereby enabling lower manufacturing costs and miniaturization of the product, and improving user convenience.