Picture of Good Electronic Circuit

Circuit Diagram Linear Optocoupler

adipgendhut@gmail.com (Unknown) — Mon, 23 Mar 2015 02:39:00 +0000

Circuit Diagram Linear Optocoupler

This linear optocoupler is built with MOC5010 and can be used to isolate a circuit from main grid, audio interface, in medical electronics and many other applications. Because of its high isolation resistance (1011 Ω), MOC5010 is used in applications where a circuit is powered directly from main power. With a bandwidth from 5 Hz to 100 kHz you have no reason to complain about audio signal response.

MOC5010 transforms an input current variation into an output voltage variation. The linear optocoupler circuit presented here has an amplification factor of 0.75. The input must not overcome 2 Vef while bandwidth is 118 kHz at -3 dB.

Amplifier A has a transfer resistance of 200 mV/mA resulting in a total amplification of 0.6 … 0.8 (-4.5 … -2 dB). The output impedance is not higher than 200 Ω so you can connect an external amplifier at pin 4. If the input voltages are higher than 2 Vef then connect a potentiometer as voltage divider like showing below optocoupler circuit diagram.

Circuit of the Linear Signal Opto-Isolator

adipgendhut@gmail.com (Unknown) — Mon, 23 Mar 2015 02:33:00 +0000

Circuit of the Linear Signal Opto-Isolator

This simple circuit provides better than 1% accuracy in optically coupling a DC voltage signal. To compensate for the non-linearity of the optical isolator, an identical device is connected in the feedback loop. To further enhance stability, both optical isolators are located inside the same IC.

Both the input and output circuits operate from single power supplies (one for the input side and a 2nd for the output side). Prior art generally requires both positive and negative power supplies –elimination of the negative power supplies simplifies the circuit.

There are numerous acceptable devices –see matrix. All these devices are current with DigiKey and most cost less than $1. Also, all are in the DIP-8 package so they may be easily plugged into a protoboard. All have CTR (current transfer ratio) ranging from 50% to about 500% –quite sloppy. What makes this work is that the two devices inside the same IC are likely matched in CTR to some degree.

Note that all these devices are not necessarily interchangeable because pin-outs vary –I found this out the hard way when I attempted to get the circuit working. Check the device data sheet if not using the specified device.

Voltage isolation issues

While DIP optical couplers have up to about 5kV isolation capability, this circuit cannot support above about 100V or so because one of the outputs is fed back to the input amplifier –this puts the voltage isolation between adjacent pins on the device rather than across the device. To maintain a high voltage rating, use two single devices and match the CTR to some degree.

Op amp selection

I generally use the LM358 dual op amp whenever I need a single ground sensing op amp. I do this because there is no DIP single device that will do the job (that I know of). There is the LM321 single op amp, but it is unpopular and comes only in the SO-23-5 SMD package. At any rate, the LM358 is very inexpensive.

Circuit operation

A positive signal input causes the output of U1 to shift positive. This causes both LEDs to conduct. U3-B turns on and provides a positive going feedback signal. When both op amp inputs are equal, the output of U1 stops integrating. At the same time the output of U3A presents a positive going signal to U2. Adjusting R2 so that R1 + R2 »4.7K causes the output of U2 to come close to the input voltage signal –further adjustment of R2 will trim for the difference in CTR so that the output voltage will exactly match the input voltage. The easiest way to test performance is to connect a DVM between input and output.

Circuit Transistors BD908 BD907 18W HI-FI Audio Amplifier TDA2030

adipgendhut@gmail.com (Unknown) — Sat, 14 Mar 2015 01:08:00 +0000

Circuit Transistors BD908 BD907 18W HI-FI Audio Amplifier TDA2030

TDA2030 + power transistors (TIP41, TIP42 or 2SC1061, 2SA761 or BD908, BD907 or BD911, BD912 or TIP31, TIP32) for an audio amplifier up to 40 Watts. Simple installation, no special settings requires and uses few components.

transistor power amplifier audio tda2030 595x446 TDA2030 + transistors BD908/BD907 18W HI FI audio amplifier and 35W driver

The amplifier is based on the TDA2030 IC and two transistors that can be (TIP41, TIP42 or 2SC1061, 2SA761 or BD908, BD907 or BD911, BD912 or TIP31, TIP32), finally you can use several pairs of transistors! The circuit around the TDA2030 is traditional to about 14-20 watts using simple supplies!

The audio output amplified by leaving the pin TDA2030 4, the transistors are active when a large flow of current through R1 and R8 pass transistors to drive and ensure high power output.

R1* R8* 1.5 = Resistor 2 Watts

R2, R3, R6 56k = Green, Blue, Orange, Gold

R4 1 = Brown, Black, Gold, Gold

R5 30k = Orange, Black, Orange, Gold – Use the 27K + 33K

R7 3.3k = Orange, Orange, Red, Gold

Capacitor’s

C1 1000µF/50V = Electrolytic Capacitor

C2, C5, C6 0.22µF = Capacitor Polyester

C3 2.2µF/50V = Electrolytic Capacitor

C4 2200µF/50V = Electrolytic Capacitor

C7 22µF/50V = Electrolytic Capacitor

C8 10µF/50V = Electrolytic Capacitor

Semiconductors

D1, D2 1N4007 or equivalent

IC1 TDA2030A – Audio amplifier integrated circuit

T1 BD908 or equivalent see text

T2 BD907 or equivalent see text

Correctors

IN Audio Input

OUT Audio Output

VCC Connector power supply

Miscellaneous

Power source, Heat sink to the IC / Transistor, Printed circuit board, Solder, speakers 50 watts 4/8 Ohms

Circuit Power Audio Amplifier Stereo with TDA7293 200 Watts

adipgendhut@gmail.com (Unknown) — Sat, 14 Mar 2015 01:00:00 +0000

Circuit Power Audio Amplifier Stereo with TDA7293 200 Watts

Amplifier circuit stereo audio with good power, using integrated circuit TDA7293 for up to 2x 100 Watts. With Suggested PCB mounting design. Includes power supply to the circuit itself, thus only requires a transformer to power. PCB compact size even being single sided. Allowing mount a power amplifier and compact with good quality, ideal for various applications.

Includes power supply on board, only requires a transformer to power the circuit.

The part of the power supply uses bridge rectifier, large electrolytic capacitors to filter values can be used since the 4.700μF to 12.000μF. The LEDs in series with the resistor and indicate on state, serve to discharge the electrolytic capacitors.

Includes circuit mute / stand-by, but was not placed key to turn on and off, is to avoid clicks in the speakers on and off, being unnecessary to use the relay output.

The power transformer can be from 18-0-18 to 33-0-33 / 200VA, with transformer with lower voltage may need less current too

Circuit Encoder Stereo Multiplexer for fm Transmitters NJM2035

adipgendhut@gmail.com (Unknown) — Sat, 14 Mar 2015 00:53:00 +0000

Circuit Encoder Stereo Multiplexer for fm Transmitters NJM2035

That codifier stereo is for who wants a system of transmission of audio stereo of high quality (hi fi). That integrated circuit produces an excellent and clear audio and a separation of excellent channel comparable with other much more expensive systems.

The heart of the circuit is the ci NJM2035 of the NJr corporation and I say that the lung of the circuit of the encoder stereo is it the crystal of quartz of 38KHz. You don’t need like this to gauge or to do any adjustment.

The circuit consists of three blocks: Pré emphasis, digital encoder and mixing apprenticeship.

Pré-emphasis of 75 µS uses a resistor of 47 k and two capacitores of 1 nF.

The second block is inside of NJM2035, it is a digital codifier

The third block is the mixer and it consists of the capacitores of 33µF and 100nF and the resistores of 82k and 10k. The objective of that circuit is multiplexar the subportadora and the pilot sign. The sign MPX comes out for CI NJM2035 pin 9. The pilot sign comes out for the pin 8 in the frequency of 19 KHz.

Circuit Audio and RF Signal Investigator LM386

adipgendhut@gmail.com (Unknown) — Sat, 14 Mar 2015 00:47:00 +0000

Circuit Audio and RF Signal Investigator LM386

The Investigator of the audio signal and RF, also known as Signal Tracer is a tool that can not miss on the bench interested in audio equipment, amplifiers either in assembly or maintenance of audio equipment. Even with simple construction, it is quite necessary to detect defects more quickly.

As a follower of the audio signal and RF, can make maintenance of equipment such as amplifiers, preamplifiers, radios, car audio, transmitters, recorders, televisions and more. The basic operation is to follow the audio signal to a point where it is not available or is undergoing any change should not occur.

Resistor’s 1/4 Watt 5%

R1 470K – Yellow, Violet, Yellow, Gold

R2 10 – Brown, Black, Black, Gold

Capacitors

C1,C6 470µF/25V – Electrolytic Capacitor

C2 100nF – Ceramic capacitor

C3, C5, C8 10µF / 25V – Electrolytic Capacitor

C4 270pF – Ceramic capacitor

C7 47nF – Polyester or Ceramic Capacitor

Semiconductors

D1 1N4004 or equivalent – silicon diode rectifier

D2 1n34or equivalent – Germanium Diode

IC1 LM386N-1 – Integrated circuit audio amplifier – Dil8

Connectors

IN Connector for RF or Audio signal input

OUT Connector for speaker

Miscellaneous

DC_9V Jack to power, connect the external power supply

P1 47K – potentiometer

BAT 9V Volt battery

S1 Key to switch between AF and RF

Solder, wire, PCI, Cash, end of tests, etc..

Circuit Adjustable Bass Filter 50 Hz to 150 Hz Ne5532

adipgendhut@gmail.com (Unknown) — Sat, 14 Mar 2015 00:41:00 +0000

Circuit Adjustable Bass Filter 50 Hz to 150 Hz Ne5532

This is a bass filter, using the OpAmp Ne5532 or another of your choice.

The circuit is simple to set up and already has symmetrical power supply, the transformer must use 9-12 volts / 500ma with center tap … In many cases the power source can be made by the power amplifier … Just watch out for the limit supported by the voltage regulators.

The circuit has two pots, one for volume adjustment and another to adjust the filter cutoff frequency of 50 to 150Hz, if you need to install the pots in a panel, use shielded wires to make connections.

Resistors 1/4 Watts 5%

R1 8.2k – Grey, Red, Red, Gold

R2,R8 150k – Brown, Green, Yellow, Gold

R3 15k – Brown, Green, Orange, Gold

R4 1k – Brown, Black, Red, Gold

R5, R6 22k – Red, Red, Orange, Gold

R7, R9 10K – Brown, Black, Orange, Gold

Capacitor’s

C1, C5, C6, C10 10n/100V – Capacitor polyester

C2, c9 2200µF/25V – Capacitor electrolytic

C3, C7 220n /100v- Capacitor polyester

C4, C8 100µF /25V – Capacitor electrolytic

C11, C12,C14, C15 47n/100V – Capacitor polyester

C13 22µF/25V – Capacitor electrolytic

Semiconductors

D1, C2, D3, D4 1N4004 or equivalent – Silicon Rectifier Diode

IC1 7912 – Integrated circuit voltage regulator positive +12 volt

IC2 7812 – Integrated circuit voltage regulator negative -12 volt

IC3 NE5532N or equivalent dual operational amplifier

Diversos

AC Connector for 9 ~12 Volts transformer with center tap

IN Input connector for stereo audio

OUT Connector to the subwoofer amplifier

P1 47k – Potentiometer for volume control

P2 47K – Double potentiometer to adjust the cutoff frequency

Solder, wire, PCI, Knob for pots, box, transformer 9-12 Volts / 500mA, etc..

Circuit Regulated Linear Power Supply LM317

adipgendhut@gmail.com (Unknown) — Sat, 14 Mar 2015 00:35:00 +0000

Circuit Regulated Linear Power Supply LM317

Normally begin to learn about electronics power supply from the battery, for example, 9 volts, 1.5 volts, 6 volts etc. But there are disadvantage that when using battery power is discharged. I need to buy a new one. Consume more.

We should the dc power supply have a choice of AC voltage. Which it must provide a output voltage as usage often is 1.5volt, 3 volts, 4.5 volts, 6v, 9v, and the current is about 1 A.

When we view many circuit ideas, found that the as figure this below (number second the power supply projects in my life) have the best fit. We use a dc voltage regulator number LM317T is the heart of the circuit. Featured, is the constant voltage. Low noise. Almost equal to the voltage of the battery. And short-circuit protection as well.

When we push power switch (S1) on, the AC-line voltage will pass through a fuse F1 and come to transformer T1 to reduce AC volts down to 12 volts
Then this current flow through the bridge diode model (D1-D4)-1N4001 to full wave rectifire as DC current and through C1 to filter current to smooth up and has C2 filter ripple signal before into LM317.
LED to display power on the circuit, with R1(2K) currents to reduce it.
The output voltage is determined by rotating a selector switch S2 a level voltage 1.5,3,4.5,5,6,9 volts respectively
C5 (10uF) control impedance and reduce a transient at output of IC1
C3 (10uF)- help to reduce the ripple before is amplified when the output voltage rise up.
C4 (0.1uF) reduce the ripple at output.
D5 and D6(1N4001) for protects IC1 from discharging of C3 and C5 respectively. In case the input of IC1 is shorted.
The maximum output current about 1.5A depends on size of the transformer We sould choose size of 2A., Or size 1A for those who want to 1A output current only.

Circuit Power Audio Amplifier Stereo TDA7293

adipgendhut@gmail.com (Unknown) — Sat, 14 Mar 2015 00:28:00 +0000

Circuit Power Audio Amplifier Stereo TDA7293

Includes power supply on board, only requires a transformer to power the circuit.

Includes circuit mute / stand-by, but was not placed key to turn on and off, is to avoid clicks in the speakers on and off, being unnecessary to use the relay output.

The power transformer can be from 18-0-18 to 33-0-33 / 200VA, with transformer with lower voltage may need less current too

Circuit Minimus Power LM3886

adipgendhut@gmail.com (Unknown) — Sat, 14 Mar 2015 00:23:00 +0000

Circuit Minimus Power LM3886

Circuit compact audio power amplifier using integrated circuit National Semiconductors LM6886TF, PCB compact, making it ideal for use where you need a compact amplifier with high power and high quality audio. Ideal for use in various applications such as, computer games, Mp3 Player, Home Theater, Surround sound, etc.

LM3886 is a single-channel, high-performance audio power amplifier IC produced by National Semiconductor (NS) company , the maximum continuous output power up to 60W, from the launched time to now, was loved by the majority of audiophiles.

The single-channel power amplifier design, a board per channel amplifier parts, amplifier board can be used in parallel.

Recommend DC dual 20-28V power supply.

MOSFET transistor

adipgendhut@gmail.com (Unknown) — Thu, 08 May 2014 00:50:00 +0000

MOSFET transistor

MOSFET transistor as its name suggests is a p type (n type) semiconductor bar (with two heavily doped n type regions diffused into it) with a metal oxide layer deposited on its surface and holes taken out of the layer to form source and drain terminals. A metal layer is deposited on the oxide layer to form the gate terminal. One of the basic applications of field effect transistor is using a MOSFET as a switch.

This type of FET transistor has three terminals, which are source, drain, and gate. The voltage applied to the gate terminal controls the flow of current from source to drain. The presence of an insulating layer of metal oxide results in the device having high input impedance.

Types of MOSFET Transistor Based on Operation Modes

A MOSFET transistor is the most commonly used type of field effect transistor. MOSFET operation is achieved in two modes, based upon which MOSFET transistors are classified. MOSFET operation in enhancement mode consists of a gradual formation of a channel whereas in depletion mode MOSFET, it consists of an already diffused channel. An advanced application of MOSFET is CMOS.

Enhancement MOSFET Transistor

When a negative voltage is applied to the gate terminal of MOSFET, the positive charge carrying carriers or holes get accumulated more near the oxide layer. A channel is formed from the source to drain terminal.

As the voltage is made more negative, the channel width increases and current flows from source to drain terminal. Thus as the flow of current ‘enhances’ with applied gate voltage, this device is called Enhancement type MOSFET.

Junction FET

adipgendhut@gmail.com (Unknown) — Thu, 08 May 2014 00:48:00 +0000

Junction FET

The Junction FET transistor is a type of field effect transistor that can be used as an electrically controlled switch. The electric energy flows through an active channel between sources to drain terminals. By applying a reverse bias voltage to gate terminal, the channel is strained so the electric current is switched off completely.

N channel JFET consists of an n type bar at the sides of which two p type layers are doped. The channel of electrons constitutes the N channel for the device. Two ohmic contacts are made at both ends of the N-channel device, which are connected together to form the gate terminal.

The source and drain terminals are taken from the other two sides of the bar. The potential difference between source and drain terminals is termed as Vdd and potential difference between source and gate terminal is termed as Vgs. The charge flow is due to flow of electrons from source to drain.

Whenever a positive voltage is applied across drain and source terminals, electrons flows from the source ‘S’ to drain ‘D’ terminal , where as conventional drain current Id flows through the drain to source. As current flows through the device, it is in on state.

When a negative polarity voltage is applied to the gate terminal, a depletion region is created in the channel. The channel width is reduced, hence increasing the channel resistance between the source and drain. Since the gate source junction is reverse biased and no current flows in the device, it is in off condition.

So basically if voltage applied at the gate terminal is increased, less amount of current will flow from the source to drain.

The N channel JFET has greater conductivity than the P channel JFET. So the N channel JFET is more efficient conductor compared to P channel JFET.

Applications of Microprocessor

adipgendhut@gmail.com (Unknown) — Thu, 08 May 2014 00:43:00 +0000

Applications of Microprocessor

These microprocessors can be used for general purpose applications or special purpose applications. The applications of microprocessors include the following:

1. General Purpose Applications

Microprocessors for general purpose applications include personal computers, single-board micro computers, super minis and Computer Aided Designs (CAD).

Personal Computers

Personal computers have 8-bit or 16-bit microprocessors. Home computers come with 8-bit microprocessor for learning programs and playing video games, whereas the computers with 16- bit microprocessor are used for business, accounts, word processing, and other purposes.

Single-Board Micro Computers

The single-board micro computers have simple hardware and software configuration and are cheaper. These micro computers are used to build small computer systems and to train students.

Super minis and CAD

32 -bit processors are used in powerful microcomputers. And, as a result, the performance of these computers is far better than the mini computers; and, these are used in engineering side as CAD machines.

2. Special Purpose Application

special purpose application includes control, communication, instrumentation, office automation and publication.

Communication

In telephone industry, microprocessors are used in modems, telephone exchanges, digital telephone sets, and also in air reservation systems and railway reservation systems both at international and national levels. Mobile phones and televisions also use microprocessors.

Instrumentation

In various instruments, microprocessors are implemented as main controllers and also used in medical instruments to measure temperature and blood pressure.

Control

Microprocessors are now available in home appliances like washing machines and microwave ovens; and, in industrial-automation sectors, microcontrollers are used to control various parameters like temperature, speed, moisture and pressure.

Publication and Office Automation

These are used in office to perform spread sheet operations, and storage. In publication, microprocessors are used in LASER printers for good speed and making automatic photo copies.

This is all about the embedded microprocessor systems and their applications. We believe that the information given in this topic is worth considering the importance of microprocessors. Please share your suggestions and opinions about this article in the comment section.

Block diagram of an embedded microprocessor

adipgendhut@gmail.com (Unknown) — Thu, 08 May 2014 00:41:00 +0000

Block diagram of an embedded microprocessor

A microprocessor chip is built by using semiconductor devices wherein thousands of transistors are integrated into a single chip for better performance. When we look at microprocessor’s history, the Pentium 4 processors have around 40-50 million transistors. The major microprocessor’s parts include:

ALU (Arithmetic Logic Unit)

Memory unit

Control Unit

Registers

System Bus

Arithmetic Logic Unit

An ALU is also known as integer unit as it is used to perform logical operations like Not, OR AND, and math calculations like add, subtract, divide, multiply and comparisons like greater then, less than, etc.

Memory Unit

Cache memory is a small amount of memory located on the chip of a microprocessor. A microprocessor stores a copy of data and instructions in its cache memory while executing the program. Types of microprocessor memory include ROM and RAM.

Control Unit

Control Unit is the brain of a microprocessor as it manages complete operations. It performs the operations like managing input, output devices, storing data and fetching instructions.

Registers

Registers are small, fast memories built into the central processing unit (CPU) to speed up its operation. General purpose registers store arbitrary data and special purpose registers control the processor.

System Bus

System bus is a single wire used to attach different components to communicate with the internal and external parts of the microprocessor. The bus receives data and instructions from the main memory, and then sends them to instruction cache and data cache. Finally these are processed and the results are again sent to the main memory through this bus

Railway Level-Crossing Gate Control With GSM

adipgendhut@gmail.com (Unknown) — Thu, 08 May 2014 00:37:00 +0000

Railway Level-Crossing Gate Control With GSM

Similar to the above project, this is also a railway level-crossing gate control system, but it is implemented by using GSM technology. In this system, the railway level crossing gate is controlled by an SMS sent by the station master or the driver to the control area.

The system has a GSM modem interfaced with a control system. When a driver or station master sends an SMS ‘open’ to the GSM modem it receives that SMS and sends it to the microcontroller. The microcontroller acknowledges these signals and sends the command signals to the motor driver IC, which controls the direction of the motor for opening and closing the gate. Therefore, this IC sends a clockwise signal to the motor to open the gate and the status gets displayed on the LCD.

In the same way, to close the gate, another SMS needs to be sent to the microcontroller. Therefore, the motor driver drives the motor in anticlockwise direction after receiving the corresponding signals from the microcontroller.

These are the two projects based on the automatic railway gate control system for the operation of gate. There are many technologies that are available to achieve this operation including Zigbee, IR, etc. Apart from this, for any help regarding any projects, you can contact us by commenting in the comment section.

Railway Level-Crossing Gate Operation

adipgendhut@gmail.com (Unknown) — Thu, 08 May 2014 00:35:00 +0000

Railway Level-Crossing Gate Operation

Automatic railway gate control system is implemented to prevent accidents of the traction system at the railway crossing levels. Nowadays many accidents take place at the railway gate crossing due to uneven crossings, even when the gate is about to close. In general, a railway gate is normally operated by a gate keeper as he receives the information about the arrival of the train.

Railway safety is the most crucial aspect of railways all over the world. This is the cheapest mode of transportation all over the world, and therefore, accidents are bound to happen due to carelessness manual operations. Therefore, an automatic railway-crossing-gate controller is used to prevent accidents at unmanned level crossings to provide much needed safety. Such efficient controllers are mostly used in remote areas that often lack the services of a station master or line man at the crossing levels.

This project is designed to control railway level-crossing gate through an Android application by the station master. This system uses Android application device for opening and closing the level-crossing gate, remotely.

Remote operation can also be achieved by any smart phone or tablet with an Android-OS with a Graphical User Interface, based on Touch Screen Operation. This system uses a microcontroller as the heart of the project, and is programmed in such a way that any control signal from the Android phone controls the motor for operating the gate.

A Bluetooth device is interfaced with this system to achieve remote operation. Station master or driver of a train can send a command from the Android application, and therefore, the Bluetooth on the mobile phone sends the signals to the Bluetooth device attached to a control circuit. At the receiver side, this Bluetooth device receives these signals and sends them to the microcontroller.

Therefore, based on the microcontroller’s program, it sends the signals to the motor driver to operate the motor. For the operation of the motor in both the clockwise and anti-clockwise directions, a motor driver is used. This system displays the message in response to the commands given by the Android applications, such as opening and closing of the gate, in the LCD.

Here, this microcontroller based project is developed by using an Android application, and it can be further improved with a provision of sending an acknowledgment about the status of the gate to the sender and including a buzzer for alerting the persons at the gate. In this way, either the driver of the train or the station master is able to send the open or close commands to the gate remotely, through an Android portable phone.

Meaning Microcontroller

adipgendhut@gmail.com (Unknown) — Thu, 08 May 2014 00:32:00 +0000

Microcontroller

microcontroller is a small computer on a single IC, which consists of memory, processor core and programmable I/O peripherals, and these are designed for embedded applications. Microcontrollers are used in automatic controlled devices like medical instruments, automobile control systems, office machines, power tools, remote controls, toys and in other embedded systems.

An AVR microcontroller is an 8-bit-RISC single-chip microcontroller. This microcontroller was developed by Atmel, in 1996; and, it was from the first microcontroller families that would use on-chip flash memory for program storage. Coming to the PIC microcontroller, it is also from a family of microcontrollers, and is made by using microchip technology. The name PIC stands for Peripheral Interface Controller. This article lists many of the microcontroller based projects that use 8051, AVR and PIC microcontrollers.

Microcontroller Based Projects on 8051

8051 Microcontroller is an 8-bit, 40-pin microcontroller based on the Harvard Architecture in which the program memory and data memory are different. This 8051 microcontroller has been in use in quite a large number of machines, because it can be easily incorporated in a project or assembled around a machine. The following are some of the projects related to this type of microcontroller:

Soft Start Induction Motor by ACPWM
Vehicle Theft Location Intimation by GPS/GSM to the Owner
Wireless Rash-Driving Detection
ACPWM Control for Induction Motor
GSM-Based Remote Monitoring of 8 Parameters of Transformer
Remotely Controlled Android Based Electronic Notice Board
Android Based Remotely Programmable Sequential Load Operation
Remote Induction Motor Control by Android Application with 7-Segment Display
Remote Operated Domestic Appliances Control by Android Application
Remote Password Operated Security Control by Android Applications
Density Based Auto Traffic Signal Control with Android Based Remote Override
Firefighting Robot Remotely Operated by Android Applications
Pick N Place Robot Arm and Movement Controlled by Android Wirelessly
Voice Controlled Robotic Vehicle with Long Distance Speech Recognition
Railway Level Crossing Gate Operation Remotely by Android Application
XBEE Based Remote Monitoring of 3 Parameters on Transformer or Generator Health
Propeller Display of Message by Virtual LEDs
Parallel Telephone Lines with Security Systems
Sine Pulse Width Modulation
Pick N Place Robot with Soft Catching Gripper
Synchronized Traffic Signals
Load Control System by Using DTMF
Movement Sensed Automatic Door Opening System
Display of Dialed Telephone Numbers on Seven-Segment Display
Line Following Robot Vehicle Using Microcontroller

Microcontroller Based Projects on AVR

The AVR microcontrollers are based on modified Harvard RISC architecture with separate memories for data and program. The speed of AVR is high when compared to the speed of 8051 and PIC microcontrollers. These microcontrollers can be tiny AVR, Mega AVR, Xmege AVR microcontrollers. The following is a list of projects based on these AVR based microcontrollers:

ATmega Based Garage Door Opening
How to Interface LED with ATmega Microcontroller
How to Interface AVR Microcontroller with PC Using USART
How to Write a Simple Boot Loader for AVR in C Language
How to Interface RFID with AVR Microcontroller
Interfacing SD Card with ATmega Microcontroller
USART with Different Frame Size Using AVR Microcontroller
How to Disable JTAG of AVR Microcontroller
Smart Home Automation Using AVR
Switch Status and LED with AVR Microcontroller
Controlling RGB LED Color Using ATmega16
Interfacing Serial Bluetooth Modem with Computer Using ATmega16
LPG Gas Detector by Using AVR Microcontroller
Green House Robot using AVR Microcontroller
Bidirectional Person Counter Using ATmega
Humidity Controller Using AVR Microcontroller
Mobile Controlled Electrical Devices Using AVR Microcontroller

PIC microcontroller

adipgendhut@gmail.com (Unknown) — Thu, 08 May 2014 00:27:00 +0000

PIC microcontroller

PIC is a Peripheral Interface Microcontroller which was developed in the year 1993 by the General Instruments Microcontrollers. It is controlled by software and programmed in such a way that it performs different tasks and controls a generation line. PIC microcontrollers are used in different new applications such as smart phones, audio accessories and advanced medical devices.

There are many PICs available in the market ranging from PIC16F84 to PIC16C84. These types of PICs are affordable flash PICs. Microchip has recently introduced flash chips with different types, such as 16F628, 16F877 and 18F452. The 16F877 costs twice the price of the old 16F84, but it is eight times more than the code size, with more RAM and much more I/O pins, a UART, A/D converter and a lot more features.

The PIC architecture consists of two memories: Program memory and the Data memory.

Program Memory: This is a 4K*14 memory space. It is used to store 13-bit instructions, or the program code. The program memory data is accessed by the program counter register that holds the address of the program memory. The address 0000H is used as reset memory space and 0004H is used as interrupt memory space.

Data Memory: The data memory consists of the 368 bytes of RAM and 256 bytes of EEPROM. The 368 bytes of RAM consists of multiple banks. Each bank consists of general purpose registers and special function registers.

The special function registers consists of control registers to control different operations of the chip resources like Timers, Analog to Digital Converters, Serial ports, I/O ports, etc. For example, the TRISA register whose bits can be changed to alter the input or output operations of the port A.

The general purpose registers consists of registers that are used to store temporary data and processing results of the data. These general purpose registers are each 8-bit registers.

Working Register: It consists of a memory space that stores the operands for each instruction. It also stores the results of each execution.

Status Register: The bits of the status register denote the status of the ALU (arithmetic logic unit) after every execution of the instruction. It is also used to select any one of the 4 banks of the RAM.

File Selection Register: It acts as a pointer to any other general-purpose register. It consists of a register file address, and it is used in indirect addressing.

Another general purpose register is the program-counter register, which is a 13-bit register. The 5 upper bits are used as PCLATH (Program Counter Latch) to independently function as any other register, and the lower 8-bits are used as the program counter bits. The program counter acts as a pointer to the instructions stored in the program memory.

EEPROM: It consists of 256 bytes of memory space. It is a permanent memory like ROM, but its contents can be erased and changed during the operation of the microcontroller. The contents into EEPROM can be read from or written to, using special function registers like EECON1, EECON2, EEDATA, etc.

PIC16 series consists of five ports, such as Port A, Port B, Port C, Port D and Port E.

Port A: It is a 16-bit port, which can be used as input or output port based on the status of the TRISA register.

Port B: It is an 8-bit port, which can be used as both input and output port. 4 of its bits when used as input can be changed upon interrupt signals.

Port C: It is an 8-bit port whose operation (input or output) is determined by the status of the TRISC register.

Port D: It is an 8-bit port, which apart from being an I/O port, acts as a slave port for connection to the microprocessor bus.

Port E: It is a 3-bit port that serves the additional function of the control signals to the A/D converter.

PIC microcontrollers consist of 3 timers, out of which the Timer 0 and Timer 2 are 8-bit timers and the Time-1 is a 16-bit timer, which can also be used as a counter.

The PIC Microcontroller consists of 8-channels, 10-bit Analog to Digital Converter. The operation of the A/D converter is controlled by these special function registers: ADCON0 and ADCON1. The lower bits of the converter are stored in ADRESL (8 bits), and the upper bits are stored in the ADRESH register. It requires an analog reference voltage of 5V for its operation.

Oscillators are used for timing generation. PIC microcontrollers consist of external oscillators like crystals or RC oscillators. In case of crystal oscillators, the crystal is connected between two oscillator pins, and the value of the capacitor connected to each pin determines the mode of operation of the oscillator. The different modes are low-power mode, crystal mode and the high- speed mode. In case of RC oscillators, the value of the Resistor and Capacitor determine the clock frequency. The clock frequency ranges from 30 KHz to 4 MHz.

A CCP module works in the following three modes:

Capture Mode: This mode captures the time of arrival of a signal, or in other words, captures the value of the Timer1 when the CCP pin goes high.

Compare Mode: It acts as an analog comparator that generates an output when the timer1 value reaches a certain reference value.

PWM Mode: It provides pulse width modulated output with a 10-bit resolution and programmable duty cycle.

Uni junction Transistor

adipgendhut@gmail.com (Unknown) — Thu, 08 May 2014 00:24:00 +0000

Uni junction Transistor

Uni junction transistor is also known as double-base diode because it is a 2-layered, 3-terminal solid-state switching device. It has only one junction so it is called as a uni-junction device. The unique characteristic feature of this device is such that when it is triggered, the emitter current increases until it is restricted by an emitter power supply. Owing to its low cost, it can be used in a wide range of applications including oscillators, pulse generators and trigger circuits, etc. It is a low-power absorbing device and can be operated under normal conditions.

1. Original Uni-junction transistor or UJT is a simple device in which a bar of N-type semiconductor material into which P-type material is diffused; somewhere along its length defining the device parameter as intrinsic standoff. The 2N2646 is the most commonly used version of UJT. UJTs are very popular in switching circuits and are never used as amplifiers. As far as Applications of UJT are concerned, they can be used as relaxation oscillators, phase controls, timing circuits and trigger devices for SCRs and triacs.

2. Complimentary Uni-junction transistor or CUJT is a bar of P-type semiconductor material into which N-type material is diffused somewhere along its length defining the device parameter as intrinsic standoff. The 2N6114 is one version of CUJT.

3. Programmable Uni-junction transistor or PUT is a close relative of thyristor; just like thyristor, it consists of four P-N layers and has anode and cathode placed at first and last layers. The N-type layer near the anode is known as anode gate. It is inexpensive in production.

The silicon bar has two Ohmic contacts designated as base1 and base2, as shown in the fig. The function of the base and the emitter are different from the base and emitter of a bipolar transistor.

The emitter is of P-type, and it is heavily doped. The resistance between B1 and B2 when the emitter is open-circuited is called an inter-base resistance. The emitter junction is usually situated closer to the base B2 than the base B1. So the device is not symmetrical, because symmetrical unit does not provide electrical characteristics to most of the applications.

The symbol for uni-junction transistor is shown in the fig. When the device is forward-biased, it is active or is in the conducting state. The emitter is drawn at an angle to the vertical line which represents the N-type material slab and the arrow head points in the direction of conventional current.

When the emitter supply voltage is increased rapidly, then the diode becomes forward-biased and exceeds the total reverse bias voltage (Ƞ VBB + VB). This emitter voltage value VE is called the peak-point voltage and is denoted by VP. When VE = VP, emitter current IE flows through the RB1 to the ground, that is, B1. This is the minimum current required for triggering the UJT. This is called the peak-point emitter current and is denoted by IP. Ip is inversely proportional to the Inter-base voltage, VBB.

Now when the emitter diode starts conducting, charge carriers are injected into the RB region of the bar. As the resistance of a semiconductor material depends upon doping, the resistance of RB decreases due to additional charge carriers.

Then the voltage drop across RB also decreases, with the decrease in resistance because the emitter diode is heavily forward biased. This in turn results in larger forward current, and as a result charge carriers are injected and it will cause the reduction in the resistance of the RB region. Thus, the emitter current goes on increasing until the emitter power supply is in limited range.

VA decreases with the increase in emitter current, and UJT have the negative resistance characteristic. The base 2 is used for applying external voltage VBB across it. The terminals E and B1 are the active terminals. UJT usually gets triggered by applying a positive pulse to the emitter, and it can be turned off by applying a negative trigger pulse.

Circuit Automatic Room Light Controller

adipgendhut@gmail.com (Unknown) — Thu, 08 May 2014 00:21:00 +0000

Circuit Automatic Room Light Controller

Nowadays without electricity we cannot imagine our daily life because electricity has become a necessity for all, without which day-to-day life chores & daily activities become stand still. Due to the depletion of non-renewable resources, conservation of energy has become mandatory and by doing so we can reduce electricity bills as well. We know that energies like wind energy, solar energy and hydro energy are called renewable energy sources which are renewable in nature. Therefore, utilization of these resources for power supply is the best possible way of producing, conserving and renewing energy, which is advantageous as it is pollution free, affordable, and free from environmental impacts.

On the other hand, the energy resources like petroleum, coal, natural gas, uranium and propane are called non -renewable resources, because their supplies are limited. Many environmental effects and day-by-day depleting energy resources warn us to save energy by using automatic room controller and energy-efficient lighting systems. Nowadays the wastage of electricity has become a routine thing for us, and the problem has become frequent at homes, schools, and colleges and even in industries. Sometimes we notice fans and lights keep on working even in the absence of people. This often happens in homes, offices and public places due to utter negligence of the inmates.

This system is designed by using two sets of IR transmitters and receivers. These IR sensors are placed in such a way that they detect a person entering and leaving the room to turn the home appliances. In this optimun energy management system, a microcontroller is the central processing unit of this project which is of 89S51 controller from the 8051 family. This system facilitates a bidirectional visitor counter for displaying the number of persons inside the room.

When a person enters into the room, an IR beam is obstructed between the IR transmitter and the receiver. This IR obstruction from the sensor-1 gives the corresponding signal to the microcontroller. The microcontroller is programmed in such a way that by the reception of the signal from the sensor-1 it turns on the fans and lights inside the room. Thus, the microcontroller gives command signals to a relay driver which turns the relays such that all these appliances turn on.

When the person leaves from this room, another set of IR sensors enable and give control signals to the microcontroller. Furthermore, similar to the above process, this system turns off the appliances like fans and lights. Apart from this, the system also takes account of the number of persons inside the room so that this control operation is varied depending on the persons’ availability in the room.

Circuit Water Level Controller

adipgendhut@gmail.com (Unknown) — Thu, 08 May 2014 00:17:00 +0000

Water Level Controller

Nowadays many houses store water in underground tanks and pump the water to the overhead tanks. At times, the water overflows from the overhead tank leading to wastage of water. To overcome this problem, a water-level indicator with an alarm system is the best option as it controls the water level to an extent that will allow reduction in wastage of water.

A Water level controller using microcontroller is a low-cost controller that is capable of managing water levels in different systems like water tanks, boilers and swimming pools, etc. Water level controller can be used in houses, industries, factories, power plants, chemical plants and other liquid storage systems to save power and money.

The above mentioned circuit consists of four probes arranged in an overhead tank and are interfaced with port 2 of the microcontroller. The probes are arranged in such a way that they sense ¼th, 1/2, ¾th and even full levels as they are placed with equal spacing one above the other with the bottom positive probe. A positive voltage supply is placed at the bottom of the overhead tank, and a full-level probe is placed in the tank and the other end is connected to the base of the transistor Q4 through a resistor R16.

Whenever the water level rises to the maximum, then current flows through the base of the transistor and the collector voltage becomes low and is interfaced with the port p2.4. The programming is done in the microcontroller and sends the data to the microcontroller and LED. D1 indicates the level of water and the motor switches off automatically whenever the water level goes below the full-level probe, and then the base of the transistor Q2 opens by switching it off; the collector voltage of Q2 is high at P2.4, which means the tank is not full and the same process is applied to the remaining sensing probes ¼, 1/2, 3/4 as they are connected to the base of the transistors q1,q2,q3 and interfaced with the ports p2.5, p2.6, and p2.7 while programming is done within the microcontroller. The LED D3, D4 and D5 glow as an indication of the levels (¼, 1/2 and empty), and then the transistor gets on and the motor will be on.

Circuit Water Level Controller

The ports P0.0, P0.1, P0.2, P0.3 and P0.4 are interfaced with the LEDs for the purpose of indicating the levels and are connected to the resistors. The port P0.5 is used to control the pump and the transistor Q6 remains on as the relay also gets activated while the port P0.7 is connected to the LED D7 as an indication of low level in the sump and the LED glows.

The tone system attached to the alarm system gives level information as ‘tank is full’ and ‘tank is empty’ so that a user can easily recognize the level of the water. As the above discussed level control is of contact type wherein the probes are in contact with liquid or water, so there is a chance of it becoming corrosive easily. This can be overcome by using a contactless sensor level measuring system which is described below.

Circuit Arduino Xmas Lights

adipgendhut@gmail.com (Unknown) — Thu, 10 Apr 2014 00:15:00 +0000

Circuit Arduino Xmas Lights

Arduino is here introduced intentionally because of its tractability which allows interested hobbyists to start their own experiments with this project for adding more light channels and/or visual effects by tweaking the hardware (Arduino + auxiliary electronics) and the software (Arduino sketch/code).

The major component, in addition to Arduino board is the LED light bar. The LED Bar is a prepackaged strip of 3 high-output LEDs powered by 12VDC. Each unit comes with a fully assembled and tested PCB with current limiting resistors, a wall-mount holder and peel-away sticky foam backing, and polarized connection wires.

Each Bar absorbs approximately 60-65mA at 12V. Here three such LED light bars (one Red, one Green and one blue) are used to complete the circuit. Use a standard 9V battery to power the arduino board, and use a suitable 12VDC adaptor for powering the light bar section as shown in the schematic diagram.

int delayTime = 0;

void setup()

{

pinMode(12, OUTPUT);

pinMode(11, OUTPUT);

pinMode(10, OUTPUT);

}

void loop()

{

delayTime = analogRead(0);

digitalWrite(12, HIGH);

delay(delayTime);

digitalWrite(12, LOW);

delay(delayTime);

digitalWrite(11, HIGH);

delay(delayTime);

digitalWrite(11, LOW);

delay(delayTime);

digitalWrite(10, HIGH);

delay(delayTime);

digitalWrite(10, LOW);

delay(delayTime);

}

Circuit LED Icicle Lights Arduino

adipgendhut@gmail.com (Unknown) — Thu, 10 Apr 2014 00:11:00 +0000

Circuit LED Icicle Lights Arduino

I had the idea of building this Arduino icicle lights project during the making of the light dimmer circuit and the result can be seen below. Is not a complicated project so it can be done easily by anyone who has an Arduino board or an Atmel microcontroller with bootloader on it.

I have used red LEDs because at the moment the white and blue ones were used in another circuits so the result is not too interesting but will definetely look fabulous with white or blue LEDs.

//Source: Picture of Good Electronic Circuit/

int pins[] = {3,5,6,9,10,11};

int leds = sizeof(pins)/2;

void setup() {

for(int thispin = 0; thispin < leds; thispin++) { pinMode(pins[thispin], OUTPUT); } } void loop() { for(int i = 0; i < leds; i++) { digitalWrite(pins[i], HIGH); if(i == 0) { // if first led delay for x ms delay(200); } if(i > 0) {

int a = i-1;

for (int t = 64; t >= 0; t--){

analogWrite(pins[a], t);

delay(5);

}

}

delay(50); // change for different drop speed

if(i == leds-1) { // if last led

delay(1000); // how long the last led stays on

// here starts the code for the fade out effect

for (int t = 255; t >= 0; t--){ // a fadding effect

analogWrite(pins[i], t);

delay(5);

}

delay(300);

// here ends the code for the fade out effect

}

Serial.println(i);

digitalWrite(pins[i], LOW);

}

}

This sketch is a bit different from the one presented in the video and has a small fade out effect on the last led. It stays on for 1000 ms, then slowly fades out and waits for 300 ms before the first led turns on again and the process is repeated over and over again.

Circuit Arduino Solar Tracker

adipgendhut@gmail.com (Unknown) — Thu, 10 Apr 2014 00:07:00 +0000

Circuit Arduino Solar Tracker

I have a standard servo that can rotate approximately 180 degrees (90° in each direction) and is controlled using the included Arduino’s Servo Library. The code is simple too and I’ll try to explain it after this video where I made a short presentation of the project in action. Unfortunately I had no solar panel at that moment.

#include

Servo myservo;

int pos = 90; // initial position

int sens1 = A0; // LRD 1 pin

int sens2 = A1; //LDR 2 pin

int tolerance = 2;

void setup()

{

myservo.attach(9); // attaches the servo on pin 9 to the servo object

pinMode(sens1, INPUT);

pinMode(sens2, INPUT);

myservo.write(pos);

delay(2000); // a 2 seconds delay while we position the solar panel

}

void loop()

{

int val1 = analogRead(sens1); // read the value of sensor 1

int val2 = analogRead(sens2); // read the value of sensor 2

if((abs(val1 - val2) <= tolerance) || (abs(val2 - val1) <= tolerance)) { //do nothing if the difference between values is within the tolerance limit } else { if(val1 > val2)

{

pos = --pos;

}

if(val1 < val2) { pos = ++pos; } } if(pos > 180) { pos = 180; } // reset to 180 if it goes higher

if(pos < 0) { pos = 0; } // reset to 0 if it goes lower myservo.write(pos); // write the position to servo delay(50); }

In the setup() function we set the pins were the LDR are connected as INPUTs and position the servo motor at 90° then wait for a 2 seconds before the code execution inside the loop(). In the loop() we read the values received from our 2 sensors and adjust the solar panel based on these values.

Amplifier Quad 40W

adipgendhut@gmail.com (Unknown) — Thu, 10 Apr 2014 00:00:00 +0000

Amplifier Quad 40W

This circuit provides a total of four speakers 4 ohms and 40W at 12v powered. It is therefore ideal for use in the car. Total harmonic distortion is rather high, about 10% at full power. But with half the power requirements (20W) is less than 2%. Anyway it is not intended to have a high performance system in the car.

With the integrated audio TDA8571J designed for automotive applications, this 40w amplifier circuit can expand the sound of the car radio or connect a portable MP3 player in it. Internally, the chip has eight operational amplifier set on the bridge, allowing each speaker terminal being energized. Dont connect the negative terminal of the mass of the speaker, because they will produce a short circuit on the output.

As usual in these kinds of development, the heat dissipation is an important factor forproper cooling to ensure stable operation, but poor ventilation can destructive circuit.Although it has an internal thermal overheating protection, is still destructive.

If you want to use it at home (not recommended), you should use a 12V source capable of draining up to 250w at 12v. Remember that filtering is a key source of success in anyaudio installation. Use a large electrolytic capacitor to eliminate riple and, in turn, foreliminate the RF ceramic capacitors.

For input using shielded cable and RCA female plugs. To connect to the car radio is recommended that you put between it and the amplifier a passive equalizer, In addition to controlling the tone voice, also can reduce in signal strength.