Posted by Circuits Arena on Thursday, 25 December 2014
Proximity Detector or Proximity Sensor Circuits is the artlcle explaining Proximity Detector : Fig. Proximity Detector Circuit Diagram. The CS209A is a bipolar monolithic integrated circuit for use in...
Proximity Detector:
Fig. Proximity Detector Circuit Diagram.
- The CS209A is a bipolar monolithic integrated circuit for use in metal
detection/proximity sensing applications.The CS209A contains an
oscillator set up by an external parallel resonant tank and a feedback
resistor connected between pin 2 and 3.
- This is a simple proximity detector using IC CS209. The internal oscillator operates close to the resonant frequency of the
tank circuit.As a metal object is brought close to the inductor, the
amplitude of the voltage across the tank gradually begins to drop. When
the envelope of the oscillation reaches a certain level, the IC causes
the outputs to toggle states.potentiometer connected between pin 1 and
8 is adjusted to achieve a certain detection distance range.
- The larger the resistance the greater the trip-point distance.Detection
range can be increased by using a high Q coil.Maximum possible range is 1
inch with a well tuned circuit.Only difficulty in making this
circuit is the tuning up the circuit to a particular range.For making
it easy place a metal piece at the desired distance from coil (with in 1
inch) and adjust resistance Rf to make one of the outputs ( pin4 or 5)
to change state. proximity sensors are now a days widely used in mobiles also.
Components list are shown above circuit diagram.
