The stepper controller circuit is very interesting, since most lines the step motor controllers are very expensive. The circuit is made of standard components and can easily be adjusted by a computer. If you cheap surplus transistors and stepper motors, the price of the circuit can be less than $ 15.
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| Stepper Motor Controller Circuit using IC 4027 |
This stepper controller circuit shown here can used to control the unipolar stepper motor, the which has four coils. The stepper controller circuit can drive for a motor current of up to about 500 MAMP / Winding by Suitable heat sinks for the SL-100 In higher currents seem 2N3055 power transistors can be used as darlington pair along with the SL-100. All diodes are used to protect the transistor from back current transients.
List Componet
R1, R2 ,R3, R4: 1K 1/4W Resistor
D1, D2, D3, D4: 1N4002 Silicon Diode
Q1, Q2, Q3, Q4: TIP31 NPN Transistor (See Notes) TIP41, 2N3055
U1 : 4070 CMOS XOR
U2 : 4027 CMOS JK Flip-Flop
S1 : SPDT Switch
Notes:
1. You should be able to substitute any standard (2N3055, etc.) power transistor for Q1-Q4.
2. Every time the STEP line is pulsed, the motor moves one step.
3. S1 changes the motors direction.
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| 4027 CMOS JK Flip-Flop IC Pinout |
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| 4070 CMOS XOR IC Pinout |