Hall effect sensor ic dn6848 from panasonic is the heart of the circuit.
Hall effect sensor circuit diagram.
When a magnetic source comes in close proximity to the hes it supplies a negative trigger pulse to the timer.
The dn6848 has a built in hall effect sensor schmitt trigger circuit power supply regulator and temperature compensation circuits integrated to a single chip.
The output signal from a hall effect sensor is the function of magnetic field density around the device.
The hall effect sensor we will use in this circuit is an a1302 hall effect sensor manufactured by allegro.
Resistor r1 acts as a positive bias for the for the input at pin 2.
When the magnetic flux density around the sensor exceeds a certain pre set threshold the sensor detects it and generates an output voltage called the hall voltage v h.
A hall effect sensor is a sensor which detects magnetic fields.
A hall effect sensor is used to trigger a timer ic.
With this circuit we will be able to detect when any mangets in proximity of our circuit.
A sensor can be used to trigger a timer for a specific duty.
If you want to use hall effect sensor with arduino board you must add 10 kilo ohms resistor between a positive electrode and an output of hall effect sensor to make the output from ic high 5 volts.
Circuit diagram using hall effect sensor.
The hall effect sensor explained above can be quickly configured through a few external parts for converting magnetic field into electrical toggling pulses for controlling a load.
1 kilo ohms resistor use as a current limiter for an led you can lower value if you want an led brighter.
Consider the diagram below.