| 摘要 |
PROBLEM TO BE SOLVED: To provide a HART analog input module that processes a plurality of channel signals using a common component, and has an input terminal for maintaining a single-ended configuration required for HART communication signal processing.SOLUTION: A HART analog input module having a differential input terminal comprises: a plurality of input terminal processing units that are coupled to a plurality of HART field devices, and when a signal having a direct current signal and a HART communication signal overlapped is input from the HART field device, detects and outputs each signal; a multiplexer that sequentially outputs the direct current signal and the HART communication signal to be output from the input terminal processing unit in accordance with a control signal; an A/D conversion processing unit that converts the direct current signal by a channel to be sequentially output from the multiplexer to a digital signal; a HART modem that demodulates a HART communication signal by a channel to be sequentially output from the multiplexer; and a control unit that provides a control signal to the multiplexer, and processes the digital signal to be output from the A/D conversion processing unit and the HART modem. |
