BY

VISHANT MALIK

A stepper motor is an electromechanical

device which converts electrical pulses into

discrete mechanical movements. The shaft

or spindle of a stepper motor rotates in

discrete step increments when electrical

command pulses are applied to it in the

proper sequence.

INTERNAL STRUCTURE OF STEPPER MOTOR

ROTOR

(permanent

magnet)

TEETH (to define

precise rotation

STATOR

(carry coil

for current

Flow)

The principle of Working of stepper motor is Electro-

Magnetism. It constructs of a rotor that is of permanent

magnet and a stator that is of electromagnets.

Now when we gives supply to stator's winding. There will

be a magnetic field developed in the stator. Now rotor of

motor that is made up of permanent magnet, will try to

move with the revolving magnetic field of stator.

Working Principle

Monoshot

2 bit counter

Gray code generator

motor

Power booster

Astable

Q1 Q0

0 00 11 01 1

Clk

Q1 Q0 A B C D

0 0 ON ON OFF OFF 11000 1 OFF ON ON OFF 01101 0 OFF OFF ON ON 00111 1 ON OFF OFF ON 1001

555 IC (2) 1KΩ (6),2.2KΩ,10KΩ resistors 1MΩ,220K pot or variable resistor 100µF capacitor,1µF, 0.01µF capacitor SL100 Transistor (4) 1N4007 (4) 7404 IC 7486 IC 7476 IC 7408 IC

To find Pulse Width,

T = 1.1 x RC.

Theoretical time period Practical ON time of motor in sec.

1. For R=250kΩT=28

2. For R=500kΩT=56

3.For R=750kΩT=82

3.For R=1000kΩT=110

Taking C=100uF