Popis: |
Analog sensors produces a variation in an electrical property to show a change in the environment. The analog variation in electrical property needs a conditioning circuit to indicate the change before conversion into digital signal. The electrical properties most commonly detected by analog sensors are voltage, current, capacitance, resistance, and charge. Real-time capacitive and resistive sensors are used in a wide range of physical measurement systems. Detection of a small capacitance or resistance change is widely demanded in industrial process control systems and medical instrumentations [2]. |