Stepper Motor Rotation ( 172.5 degree angle ) without any Microcontroller

Stepper motor is an electronics device and a brushless DC electric motor that divides a full rotation into a number of equal steps. It is widely used in robotics, industry, computer peripherals, motion control, business machines and many other purpose. 

There are many techniques for rotating stepper motor. We need to rotate motor any angle that we want. We know that stepper motor is one kind of digital device or digital motor, for rotating this need sequential clock pulse to the specified coil of the motor. For rotating 360 degree angle need specific number of clock pulse which is depends on the number of coil and its mechanism. 

Most of the people use microcontroller for rotating stepper motor any angle and speed. Using microcontroller, stepper motor’s speed control and any angle rotation is very easy, accurate and flexible work. For microcontroller must need to know assembly or embedded C language. 

The students who are new or beginners, does not know these language is very difficult to make project related to stepper motor rotation. This topics will help them to solve the problem without having microcontroller knowledge. Because the topics is “stepper motor rotation any angle without microcontroller.” 

Though it is quite hard, students will be benefited by this hobby project. This project is fully hardware implemented and design is complicated on the clock IC section. The following project description is given bellow – 

Required instruments:

1. Timer IC- 555 timer – 1pcs
2. Flip-flop IC – 74109 - 1pcs
3. Clock IC – 7490 – 2pcs
4. AND gate IC – 7408 – 1pcs
5. Jonson Counter – 4017 – 1pcs
6. Motor driver IC – 293 -1pcs
7. Relay – 6 volt – 1pcs
8. Transistor – BC547 -1pcs
9. Resistors – 150k, 10k and 1k - 2pcs
10. Capacitors – 4.7 uF, 10nF
11. Diodes – 4148 – 1pcs
12. IC driver voltage – 5 Volt
13.       Motor driver voltage – 9 Volt

Stepper Motor:

These stepper motor have 4 pin so have 2 coil. Pin-1 and Pin-3 have one coil. Pin-2 and Pin-4 have another coil. Motor have 48 steps so need 48 pulse for 360 degree rotation. So motor rotate 7.5 degree angle per step or per pulse. The stepper motor internal coil configuration is given bellow:

 So the pulse sequence will be Pin-1, Pin-2, Pin-3 and Pin-4. The stepper motor is connected to motor driver IC 293. 

Motor Driver IC:

For driving motor, need huge current. Jonson counter IC cannot deliver huge current to operate the stepper motor. For this reason motor driver ic is needed. IC293 is called motor driver ic which need 2 different voltage one is 5 volt and the other is motor driving voltage 9 Volt or 12 Volt.  Pin-9 will be connected to 9 Volt or 12 Volt and Pin-16 will be connected to 5Volt. Pin-1 and Pin-9 will be short and connected to 5volt with 10k resistor. Pin-4, 5, 12, 13 is connected to ground. Pin- 3, 6, 11, 14 are output and Pin- 2, 7, 10, 15 are input which are connected with 2^nd Jonson counter IC 4017. 

Clock Pulse Generator:

This is the 555 timer based clock pulse generator which is called astable(free running) multivibrator. The output frequency is 1Hz which is fed to the Jonson counter (both IC Pin- 14) and clock IC (first IC Pin-14).

2^nd Jonson counter (HC4017):

Jonson counter is a decade counter which have ten output pin and one input clock pulse pin. When clock pin-14 get pulse then the counter deliver pulse sequentially to the ten output pin. Here we need only 4 pin so the reset Pin-15 will be connected to Pin-10. So the four output pin of the counter are Pin-3, 2, 4, and 7 sequentially. Which will be connected directly with motor driver ic.

 N.B: Jonson counter ic driving voltage must be 5volt.

1^st Jonson counter (HC4017):

Similar to 2^nd Jonson counter only the difference is 1^st Jonson counter’s output will be connected inversely to the 2^nd Jonson counter’s output. Clock Pin- 14 of both ic will be connected to the clock pulse generator IC 555 output Pin-3.

N.B: Pin-16 of both IC are voltage pin connected to the 6 Volt relay. 6Volt relay supply the voltage alternatively to the two Jonson counter IC.

Clock IC (SN74LS90N):

SN74LS90N is mainly counter IC used for making digital clock in laboratory work that’s why it is popular as clock ic. Two 7490 are using here to get 23 pulses for rotating 172.5 degree angle. AND Gate IC (7408) is also used here. This circuit diagram is given bellow:

 N.B: If you need to know how it works please visit here. IC driving voltage must be +5volt if greater ic not work accurately.

Flip-flop (74109):

This is the  flip-flop IC which is configured as a T flip-flop. T flip-flop output depends on the input (which is come from the 7409 ic). Pin-2 and 3 is connected to the output of the SN74LS90N IC. And the output pin-6 is connected to the transistor BC547.

When input is 1 the output is 1 and when input is 1 the output is 0. Again

When input is 1 the output is 1 and when input is 1 the output is 0.

 If is most important that every 23^th pulse clock IC(SN74LS90N) give one pulse. So the output of the Flip-flop will be 1 and 0 alternatively on every 23^th pulse. Using this technique transistor will be ON and OFF according to Flip-flop output. And also active and de-active the relay alternatively.

Relay:

The main function of relay is to supply the positive voltage (+5volt) alternatively to the Jonson counters (Pin-16). When 1^st Jonson counter (HC4017) will get the voltage, the motor rotate 172.5 degree clockwise direction and when 2^st Jonson counter (HC4017) will get voltage, the motor rotate 172.5 degree anti-clockwise direction. 

Any Angle:

By changing clock IC pulses we can change the angle of the motor rotation.

555 Timer Touch Activated Alarm Circuit Diagram

This is the circuit diagram of touch activated alarm system which still activated on load shedding. Alarm system will be activated when someone touch the “touch plate” which is called trigger. In this circuit the most updated part is automatic battery activator which is made by a relay. So don’t upset on load shedding you alarm system is activated. This circuit could be used at your home door, locker, vehicle or metal gate etc.

4017 LED Knight Rider Running Light Circuit Diagram

In this  4017 Knight Rider circuit, the 555 timer is wired as an oscillator. It can be adjusted to give the desired speed for the display. The output of the 555 is directly connected to the input of a Johnson Counter (CD 4017).

 The input of the counter is called the CLOCK line. The 10 outputs become active, one at a time, on the rising edge of the waveform from the 555. Each output can deliver about 20mA but a LED should not be connected to the output without a current-limiting resistor (220Ω in the circuit above).

The first 6 outputs of the chip are connected directly to the 6 LEDs and these “move” across the display. The next 4 outputs move the effect in the opposite direction and the cycle repeats. The animation above shows how the effect appears on the display. Using six LEDs, the display can be placed in the front of a model car to give a very realistic effect. The outputs can be taken to driver transistors to produce a larger version of the display.

Freeze Protector Circuit

This is the simple freeze protector circuit diagram. It is also called timing circuit. It is just hobby project for beginners. When you need to operate automatically any device in the fixed time later after coming AC power supply, you can use this circuit. 

The voltage amplitude is high when AC power come. Suddenly high voltage destroys the electronics device. For this reason, in the time of load shedding we need to switched off electronics device (Audio/Video player, CD/DVD Player, TV, Freeze or any electronics device). This circuit solve this problem.

Hobby Electronics helps the beginners to know the timing circuit specially using 555 IC timer. NE555 IC is the very simple well known parts. Its configuration is very simple. You can use this timer any simple circuit. 

In this circuit use 12volt power supplies. 300k variable resistor is used for timing control. Timing resistor and capacitor are 300k and 1000uF. Only change the value of the variable resistor for your required timing. 

The circuit output pin 3 is connected with resistor (10k) and output 12 volt relay. Relay is connected as figured with the device. Making cost is too low. Anyone can make this circuit easily.

Frequency Meter Circuit

This is the circuit of frequency meter. It measures the frequency of the input signal in terms of current passing through an ordinary ammeter. The main component of this circuit is the 555, a versatile, general-purpose timer IC. In this circuit, the 555 is configured as a monostable multivibrator that outputs a single pulse at pin 3 every time the input signal at pin 2 goes 'low'.

The width of the output pulse generated by the 555 is defined by R3 and C3.  The larger the output pulse width, the longer is the time that pin 3 is high. Since pin 3 doesn't sink current when it is high, the current passing through the ammeter is higher when pin 3 is high.

This means that the larger the values of R3 and C3 are, the larger is the output pulse width, and the higher is the current passing through the ammeter for a given input frequency.For any given value of R3 and C3, on the other hand, the current passing through the ammeter increases as the input frequency increases.

This is because pin 2 is 'retriggered' more often as the input frequency increases, decreasing the total duration wherein the output is 'low'.  Thus, the ammeter dial in this circuit would be a good indicator of the relative frequency of the input signal at pin 2. Good choices for the values of R3 and C3 to match the intended application as well as careful calibration through R5 are required to make this simple circuit work properly.