| 摘要 |
PURPOSE: An analog front end circuit is provided to implement a small size, low consumption power, and low costs. CONSTITUTION: An analog front end circuit (30) for measurement comprises an insulation unit (31), a non-insulation unit (32), and an insulation communication unit (33). The insulation unit includes an analog to digital (AD) conversion circuit (313) managing an interface and a sensor. The non-insulation unit includes a control circuit (321) managing the interface of the control device. The insulation communication unit executes half-duplex insulation communication between the insulation unit and the non-insulation unit. A control circuit transmits an AD conversion execution command for an AD conversion circuit for the insulation unit. The control circuit transmits an AD conversion result to the control device by obtaining the AD conversion result through the insulation communication unit. [Reference numerals] (10) Sensor; (20) Main controller; (31) Insulation unit; (314) Setup monitor resistor; (315) Communication circuit; (316) Clock regeneration circuit; (317) DC-DC converter; (32) Non-insulation unit; (321) Control circuit (CPU); (322) Memory; (323) Communication unit; (324) Communication circuit; (325) Other peripheral circuits; (328) Transformer driver; (33) Insulation communication unit; (330) Transformer for insulation communication; (34) Transformer for insulation power supply; (351) Protective SW; (AA) Insulation; (BB) Internal power supply |
