led matrix and relay interfacing part-3
Post on 18-Aug-2015
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LEDs are arranged in rows and columns in a matrix format. we can address each LED by row and column. Led matrices are of types. Common-row anode and common-row
cathode. With common-row anode current sources (positive voltage) are attached to rows and currents sink (negative voltage, ground) to columns.
With common-row cathode current sinks are attached to rows and currents source to columns
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A relay is an electromechanical device that uses small electrical currents and voltages to control larger electrical currents and voltages.
The heart of a relay is an electromagnet (a coil of wire that becomes a temporary magnet when electricity flows through it).
Relays bridge the gap, making it possible for small currents to activate larger ones.
That means relays can work either as switches (turning things on and off) or as amplifiers (converting small currents into larger ones).
www.techvilla.org.in
www.techvilla.org.in
When power flows between points V1 and V2,it activates magnetic field in the coil.
The magnetized coil attracts the contact which then activates the second circuit.
When the power is switched off, a spring pulls the contact back up to its original position, switching the second circuit off again.
www.techvilla.org.in
www.techvilla.org.in
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