Electronic Engineering projects :-----Wireless Stepper Motor Controller Using Infrared Signal


Ø 3.0mm Round Type Infrared LED
Ø High Reliability
Ø Peak Wavelength at 940, 880, 850nm
Ø Water Clear, yellow Transparent, Blue Transparent available
Ø IC compatible /Low current capability


Free air transmission system
Ø Infrared remote control units with high power requirement
Ø Smoke detector
Ø Infrared Camera
Ø Infrared applied system


·        A wireless stepper motor controller using infrared signals. Using this circuit we can control the stepper motor from a distance of up to four meters.

·        The circuit comprises transmitter and receiver section. The communication between the transmitter and receiver sections is achieved through infrared signals.




Block diagram

Circuit diagram

Power distributed circuit

Working of circuit

List of component
·       IC 555
·       RESISTOR
·       74LS74
·       ULN 2003
·       IR LED
·       TSOP1738
·       Transformer:
·       Regulated IC:




A stepper is a DC motor .it has a two coil. For start the motor we need step by step supply in both coils so we can get step by step supply using this project. And using this project we can control the stepper motor by remote a long distance. A IR LED give a signal and TDOP1738 sensor sense the signal and give clock plus to 74LS74 flip flop IC and its output is apply to ULN2003 it is a stepper motor driver its amplify this signal and give to stepper motor and motor is run.

Block Diagram

Circuit Diagram



Power distributed circuit:

·        An Ac powered unregulated power supply usually uses a transformer to convert voltage from the wall outlet (mains) to a different, now a day usually lower voltage.
·        If it is used to produce DC, a rectifier is used to convert alternating voltage to a pulsating direct voltage, followed by a filter, comprising one or more capacitors, resistors and sometime inductors, to filter out (smooth) most of the pulsation.
          We used ICs to produce the voltage regulator. 


A wireless stepper motor controller made infrared signal. Using this circuit we can control the stepper motor from a distance of up to four meters.
The circuit comprises transmitter and receiver section. The communication between the transmitter and receiver sections is achieved through infrared signals. Thus on reception of every clock pulse, the high output keeps shifting in a ring fashion. Here is a low-cost and simple wireless stepper motor controller using infrared signals. Using this circuit you can control the stepper motor from a distance of up to four meters.

The circuit comprises transmitter and receiver sections. The communication between the transmitter and receiver sections is achieved through infrared signals.

In the transmitter section, timer NE555 IC is configured as actable multi vibrators with frequencies of around 1 Hz and 38 kHz, respectively. The output of IC1 is given to reset pin 4 of IC2, so the 38 kHz carrier signal is modulated by 1Hz modulating signal. The modulated signal from pin 3 of IC2 is transmitted by the infrared LED.  Resistor R5 limits the current through the IR LED.

The transmitted signal is sensed by IR receiver module TSOP1738 (IC6) of the receiver section and its output at pin 3 is used as clocks for dual flip-flop 74LS74 Ices (IC3 and IC4), which are configured as a ring counter.
When the power is switched on, the first flip-flop is set and its Q1 output goes high, while the other three flip-flops are reset and their outputs go low. On receiving the first clock pulse, the high output of the first flip-flop gets shifted to the second flip-flop

The outputs of flip-flops are amplified by the Darlington transistor array inside ULN2003 (IC5) and connected to the stepper motor windings marked ‘A’ through ‘D.’ The common point of the windings is connected to +12V DC supply.

To stop the motor, the flip-flops can be reset manually by pressing reset switch S1. On releasing the reset switch, the stepper motor again starts moving. If any interruption occurs between the transmitter and the receiver, the motor stops.


·      IC 555

The 555 timer IC is an integrated circuit (chip) used in a variety of timer, pulse generation, and oscillator applications. The 555 can be used to provide time delays, as an oscillator, and as a flip-flop element. Derivatives provide up to four timing circuits in one package.
·      Pins

Ion of the pins for a DIP package is as follows:
Ground reference voltage, low level (47)
The OUT pin goes high and a timing interval starts when this input falls below 1/2 of CTRL voltage (which is typically 1/3 of VCC, when CTRL is open).
This output is driven to approximately 1.7 V below +VCC or GND.
A timing interval may be reset by driving this input to GND, but the timing does not begin again until RESET rises above approximately 0.7 volts. Overrides TRIG which overrides THR.
Provides "control" access to the internal voltage divider (by default, 2/3 VCC).
The timing (OUT high) interval ends when the voltage at THR is greater than that at CTRL (2/3 VCC if CTRL is open).
Open collector output which may discharge a capacitor between intervals. In phase with output.
Positive supply voltage, which is usually between 3 and 15 V depending on the variation.
Mono stable
RC circuit
Schematic of a 555 in mono stable mode

The relationships of the trigger signal, the voltage on C and the pulse width in mono stable mode In the mono stable mode, the 555 timer acts as a "one-shot" pulse generator. The pulse begins when the 555 timer receives a signal at the trigger input that falls below a third of the voltage supply. The width of the output pulse is determined by the time constant of an RC network, which consists of a capacitor (C) and a resistor (R). The output pulse ends when the voltage on the capacitor equals 2/3 of the supply voltage. The output pulse width can be lengthened or shortened to the need of the specific application by adjusting the values of R and C

The output pulse width of time t, which is the time it takes to charge C to 2/3 of the supply voltage, is given by
Where t is in seconds, R is in ohms and C is in farads.
While using the timer IC in mono stable mode, the main disadvantage is that the time span between any two triggering pulses must be greater than the RC time constant.
 A stable

Standard 555 a stable circuit
In a stable mode, the 555 timer puts out a continuous stream of rectangular pulses having a specified frequency. Resistor R1 is connected between VCC and the discharge pin (pin 7) and another resistor (R2) is connected between the discharge pin (pin 7), and the trigger (pin 2) and threshold (pin 6) pins that share a common node. Hence the capacitor is charged through R1 and R2, and discharged only through R2, since pin 7 has low impedance to ground during output low intervals of the cycle, therefore discharging the capacitor.
In the stable mode, the frequency of the pulse stream depends on the values of R1, R2 and C:

The high time from each pulse is given by:
And the low time from each pulse is given by:
Where R1 and R2 are the values of the resistors in ohms and C is the value of the capacitor in farads.
The power capability of R1 must be greater than .Particularly with bipolar 555s, low values of  must be avoided so that the output stays saturated near zero volts cycle.
during discharge, as assumed by the above equation. Otherwise the output low time will be greater than calculated above. It should be noted that the first cycle will take appreciably longer than the calculated time, as the capacitor must charge from 0V to 2/3 of VCC from power-up, but only from 1/3 of VCC to 2/3 of VCC on subsequent cycles.
To achieve a duty cycle of less than 50% a small diode (that is fast enough for the application) can be placed in parallel with R2, with the cathode on the capacitor side. This bypasses R2 during the high part of the cycle so that the high interval depends approximately only on R1 and C. The presence of the diode is a voltage drop that slows charging on the capacitor so that the high time is longer than the expected and often-cited ln(2)*R1C = 0.693 R1C. The low time will be the same as without the diode as shown above. With a diode, the high time is
Where Diode is when the diode has a current of 1/2 of Vic/R1 which can be determined from its datasheet or by testing. As an extreme example, when Vic= 5 and Diode= 0.7, high time = 1.00 R1C which is 45% longer than the "expected" 0.693 R1C. At the other extreme, when Vic= 15 and Diode= 0.3, the high time = 0.725 R1C which is closer to the expected 0.693 R1C. The equation reduces to the expected 0.693 R1C if Diode= 0.
The operation of RESET in this mode is not well defined, some manufacturers' parts will hold the output state to what it was when RESET is taken low, and others will send the output either high or low.

Resistor is an electrical component that reduces the electric current. The resistor's ability to reduce the current is called resistance and is measured in units of ohms (symbol: Ω).If we make an analogy to water flow through pipes, the resistor is a thin pipe that reduces the water flow.

Capacitor is an electronic component that stores electric charge. The capacitor is made of 2 close conductors (usually plates) that are separated by a dielectric material. The plates accumulate electric charge when connected to power source. One plate accumulates positive charge and the other plate accumulates negative charge. The capacitance is the amount of electric charge that is stored in the capacitor at voltage of 1 Volt. The capacitance is measured in units of Farad (F).
The capacitor disconnects current in direct current (DC) circuits and short circuit in alternating current (AC) circuits.

Dual D-type flip-flop with set and reset; positive edge-trigger

The 74HC74 and 74HCT74 are dual positive edge triggered D-type flip-flop. They have
Individual data (nD), clock (nCP), set (nSD) and reset (nRD) inputs, and complementary
nQ and nQ outputs. Data at the nD-input, that meets the set-up and hold time
Requirements on the LOW-to-HIGH clock transition, is stored in the flip-flop and appears at
The nQ output. Schmitt-trigger action in the clock input makes the circuit highly tolerant to
Slower clock rise and fall times. Inputs include clamp diodes that enable the use of current
Limiting resistors to interface inputs to voltages in excess of VC.



The ULN2001A, ULN2002A, ULN2003 and
ULN2004A are high voltage, high current Darlington
Arrays each containing seven open collector Darlington
Pair with common emitters. Each channel
Rated at 500mA and can withstand peak currents of
600mA. Suppression diodes are included for inductive
Load driving and the inputs are pinned opposite
The outputs simplify board layout.
The four versions interface to all common logic families
ULN2001A General Purpose, DTL, TTL, PMOS,
ULN2002A 14-25V PMOS
These versatile devices are useful for driving a wide
Range of loads including solenoids, relays DC motors,
LED displays filament lamps, thermal print heads
And high power buffers.
The ULN2001A/2002A/2003A and 2004A are supplied
in 16 pin plastic DIP packages with a copper
Lead frame to reduce thermal resistance. They are
Available also in small outline package (SO-16) as

TSOP 1738

The TSOP1738 series are miniaturized receivers for infrared remote control systems PIN diode and preamplifier are assembled on lead frame the epoxy package is designed as IR filter. 



·         STEPPER MOTOR – 

an electromagnetic actuator. It is an incremental drive (digital) actuator and is driven in fixed angular steps.
·        This means that a digital signal is used to drive the motor and every time it receives a digital pulse it rotates a specific number of degrees in rotation.
·      Each step of rotation is the response of the motor to an input pulse (or digital command).
· Step-wise rotation of the rotor can be synchronized with pulses in a command-pulse train, assuming that no steps are missed, thereby making the motor respond faithfully to the pulse signal in an open-loop manner.

· Stepper motors have emerged as cost-effective alternatives for DC servomotors in high-speed, motion-control applications (except the high torque-speed range) with the improvements in permanent magnets and the incorporation of solid-state circuitry and logic devices in their drive systems.
·      Today stepper motors can be found in computer peripherals, machine tools, medical equipment, automotive devices, and small business machines, to name a few applications.
Stepper motors are usually operated in open loop mode.




•Position error is noncumulative. A high accuracy of motion is possible, even under open-loop control.
•Large savings in sensor (measurement system) and controller costs are possible when the open-loop mode is used.
•Because of the incremental nature of command and motion, stepper motors are easily adaptable to digital control applications.
•No serious stability problems exist, even under open-loop control.
•Torque capacity and power requirements can be optimized and the response can be controlled by electronic switching.
•Brushless construction has obvious advantages.


•They have low torque capacity (typically less than 2,000 oz-in) compared to DC motors.
•They have limited speed (limited by torque capacity and by pulse-missing problems due to faulty switching systems and drive circuits). •They have high vibration levels due to stepwise motion.
•Large errors and oscillations can result when a pulse is missed under open-loop control. 



The above figure is the cross-section view of a single-stack variable-reluctance motor. The stator core is the outer structure and has six poles or teeth. The inner device is called the rotor and has four poles. Both the stator and rotor are made of soft steel. The stator has three sets of windings as shown in the figure. Each set has two coils connected in series. A set of windings is called a “phase”. The motor above, using this designation, is a three-phase motor. Current is supplied from the DC power source to the windings via the switches I, II, and, III.

Starting with state (1) in the upper left diagram, note that in state (1), the winding of Phase I is supplied with current through switch I. This is called in technical terms, “phase I is excited”. Arrows on the coil windings indicate the magnetic flux, which occurs in the air-gap due to the excitation. In state I, the two stator poles on phase I being excited are in alignment with two of the four rotor teeth. This is an equilibrium state.
Next, switch II is closed to excite phase II in addition to phase I. Magnetic flux is built up at the stator poles of phase II in the manner shown in state (2), the upper right diagram. A counter-clockwise torque is created due to the “tension” in the inclined magnetic flux lines. The rotor will begin to move and achieve state (3), the lower left diagram. In state (3) the rotor has moved 15°.

When switch I is opened to de-energize phase I, the rotor will travel another 15° and reach state (4). The angular position of the rotor can thus be controlled in units of the steep angle by a switching process. If the switching is carried out in sequence, the rotor will rotate with a stepped motion; the switching process can also control the average speed.
The above motor is a two-phase motor. This is sometimes called UNIPOLAR. The two-phase coils are center-tapped and in this case they the center-taps are connected to ground. The coils are wound so that current is reversed when the drive signal is applied to either coil at a time. The north and south poles of the stator phases reverse depending upon whether the drive signal is applied to coil 1 as opposed to coil 2. 


There are three modes of operation when using a stepper motor. The mode of operation is determined by the step sequence applied. The three step sequences are:
Full H = HIGH = +V
Half Stepping L = LOW = 0V


The wave stepping sequence is shown below.
STEP L1 L2 L3 L4
1 H L L L
2 L H L L
3 L L H L
4 L L L H
Wave stepping has less torque then full stepping. It is the least stable at higher speeds and has low power consumption.


The full stepping sequence is shown below.
STEP L1 L2 L3 L4
1 H H L L
2 L H H L
3 L L H H
4 H L L H
Full stepping has the lowest resolution and is the strongest at holding its position. Clock-wise and counter clockwise rotation is accomplished by reversing the step sequence.
The half-step sequence is shown below.
STEP L1 L2 L3 L4
1 H L L L
2 H H L L
3 L H L L
4 L H H L
5 L L H L
6 L L H H
7 L L L H
8 H L L H
The half-step sequence has the most torque and is the most stable at higher speeds. It also has the highest resolution of the main stepping methods. It is a combination of full and wave stepping. 


Transformer convert AC -240 V to AC-12 V.

RM0513 is a general purpose chassis mounting mains transformer. Transformer has 240 V primary windings and centre tapped secondary winding. 
The transformer has flying colored insulated connecting leads (Approx 100 mm long). The Transformer act like as step down transformer reducing AC - 240V to AC - 12V. 
The Transformer gives two outputs of 24V, 12V and 0 V. The Transformer’s construction is written below with details of Solid Core and Winding. 
The transformer is a static electrical device that transfers energy by inductive coupling between its winding circuits. 

A varying current in the primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic flux through the secondary winding. This varying magnetic flux induces a varying electromotive force (E.M.F) or voltage in the secondary winding. 

The transformer has cores made of high permeability silicon steel. The steel has a permeability many times that of free space and the core thus serves to greatly reduce the magnetizing current and confine the flux to a path which closely couples the windings.

The solid core uses one of the common design of laminated core is made from interleaved stacks of E - shaped steel sheets capped with I - shaped pieces, leading to its name of 'E - I transformer’. Such a design tends to exhibit more losses, but is very economical to manufacture. Windings are arranged concentrically to minimize flux leakage. 

The effect of laminations is to confine eddy currents to highly elliptical paths that enclose little flux, and so reduce their magnitude. Thinner laminations reduce losses, but are more laborious and expensive to construct. Thin laminations are generally used on high-frequency transformers, with some of very thin steel laminations able to operate up to 10 K Hz.

Regulated IC:

·        Voltage regulator, usually having three legs, converts varying input voltage and produces a constant regulated output voltage. They are available in a variety of outputs.
·        The LM78XX series typically has the ability to drive current up to 1A. for application requirements up to 150mA, 78LXX can be used.
·        As mentioned above, the component has three legs: input leg which can hold up to 36VDC common leg (GND) and an output leg with the regulators voltage. For maximum voltage regulation, adding a capacitor in parallel between the common leg and output is usually recommended. Typically a 0.1MF capacitor is used.

·     1.  From this project, I study abut wireless stepper motor control.

·     2. I also study about IC 555 with its various modes & application in detail.

·    3.  I also study about IC 74LS74 and stepper motor driver ULN 2003 and stepper motor with its various modes & application in detail.