Introduction: 555 TIMER CIRCUIT TO DRIVE a STEPPER MOTOR
It all began when I purchased some TB6560 V20 stepper motor driver boards, for a 3 axis engraver that I am building, Two boards arrived with two broken switches, and, I wanted to know if the boards were functioning properly, the safest way was to develop a pulse circuit to drive the board, by using a 555 timer. the circuit was a success and I found that the Driver boards were functioning properly. When I informed the seller at Ebay he refunded 25% of the cost...
It also gives you the opportunity of driving a stepper motor like all other motors, without micro controllers, Hybrid stepper motors produce high torque at low speeds and can be used in many fields without gearing..
Step 1: THE 555 CIRCUIT
Usually a stepper Motor is rotated with a driver,and,the driver is driven by pulses from a microcontroller,
A simple way to test a stepper motor driver or stepper motor is to generate pulses using a 555 timer. In this demonstration, a 555 timer is constructed to generate two frequencies which can be chosen by a switch, one low frequency of about 1Hz and one at around 100Hz. Faster speeds could be generated by changing the capacitor from 0.1UF to 0.01UF or 0.001UF, the speed could also be controlled by adjusting the 100k Variable resistor. pictured here is the basic circuit diagram. in its first stage of construction. I presume you have a basic knowledge of electronics and have had some basic experience in wiring on vero board. hence I will only provide pictures of the wired board.
The entire circuit is powered by a step down electronic transformer, in addition to the basic timer circuit that is displayed in the drawing the following have been added.
1. A two way switch for switching capacitors.
2. A two way switch for switching + 5volts and GND for the CW direction signal.
3. A 5 Volt regulator 7805 for operating the 555 timer and for the high and low (Binary) signals for the stepper Driver board.
4. A regulated 12 volt supply using a 7812 regulator. this is for driving the stepper motor..
All the additions are labelled and shown in the picture that is displayed.
Step 2: CONNECTING THE DRIVER BOARD AND THE STEPPER MOTOR
The connections to the driver board are shown in the picture, note the following
1. the enable signal is GND or Zero which is applied to the EN- . Applying a + signal to the + EN will stop the rotation.
2. CW - is given to GND and CW+ is given a binary 1 or 0 to turn clockwise or anticlockwise this signal is given via
a two way switch which is shown in the picture.. Binary 1 is +5 volts and binary 0 is GND.
3. The pulse signal from pin No.3 of the 555 timer, is given to CLK + and CLK - is given a GND connection.
4. The motor connections are given to the stepper motor usually Red & Blue and Green & Black are the colour of the wires where BLACK is + GREEN is - and BLUE is - and RED is +
5. The other two motor connections is for the motor power supply in this case, I have given it a regulated +12 volts from the 7812 regulator, the other terminal is given a GND connection.
The video shows when the circuit is switched on, note the direction of the stepper motor can be changed by using the spring loaded two way switch.. SO THAT IS IT HAPPY STEPPING....