Simple Proximity Detector
How to make a simple Proximity detector or sensor
Description
This is a simple proximity detector using IC CS209. 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 & 3 .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 & 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 Detector Circuit Diagram
Simple Proximity Detector Circuit
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i read the circuit now so i test this circuit working good then i will tell
hmmmmm……. nyc……. i was just looking for this… how can we increase the proximity more than one inch……??
Hi Reddy this chip is obsolete and no more available and there is no equivallent also.
you may try the following link
http://www.electronic-circuits-diagrams.com/sensorsimages/sensorsckt4.shtml
http://www.lynx-india.com/shop/index.php?productID=4948
http://www.shareapic.net/View-19665911-Circuits.html
Some i tried here in bangalore for the IC CS209a but in vain. can any body help me where i can get it.
my mail id
pls. send me gold detector diagram which is applicable or intended to philippine condition
Hi could this application be used to activate a cat flap type lock? would it detect a metal bell on the cats collar.
Thanks Dave
I am not sure. We need to experiment.
hello, i need a simple opamp741 circuit that i can make for a college project please reply on lilac1111@gmail.com
thank you for sharing your adea about this proximity detector. it have a great use to me in getting reed of burglars.
hello. I have need to metal(gold) detector circuit .
please… send schematic . very very tanx . i live in iran .
there are many metal detector circuits in the site itself.pls have a look