Showing posts with label using. Show all posts

Tuesday, November 18, 2014

Triangle Square Wave Generator Using Op Amp

The circuit shows a simple triangle and square wave generator with a common dual operational amplifier LM1558 to produce very low frequencies around 10 kHz. The time interval for one half cycle is about R * C and outs of supply of 10 mA. The amplitude of the triangle can be altered by adjusting the 47K and waveform offset can be eliminated by adding a capacitor in series with the output.

Saturday, November 8, 2014

Dark Sensitive Power Switch Circuit Diagram Using LDR

DescriptionCircuit showing a Dark Sensitive Power Switch .Here we have used a ldr and a ordinary transistor for making this circuit
.Connect any 230 volt equipment at the load .You need a 9 volt power supply
Components Required

Resistor 10 k , 680 R

Transistor BC 548

Diode IN 4007

Relay LDR

Wednesday, October 29, 2014

Low voltage DC motor speed control circuit using TDA7274

Description.
Here is the circuit diagram of a low voltage /low power DC motor speed controller based on the IC TDA 7274 from ST Microelectronics. The IC TDA 7274 is a monolithic integrated DC motor speed controller intended for low voltage/ low power applications. Built in internal voltage reference voltage, wide input voltage range (1.8 t0 6V), high linearity, 700mA output current, excellent temperature stability etc make this IC well suitable for almost all low power DC motor speed control applications.
The motor to be controlled is connected between pin3 (Vs) and pin4 (output) of the IC. Resistor network comprising of R1, R2, and R3 is the section that deals with the speed control. Control pin (pin8) of the IC is connected to the junction of R2 and R3 and the speed of the motor varies linearly according to the position of POT R3. Capacitor C1 rectifies the fluctuations in motor speed and capacitor C2 cancels the motor spikes.

Notes.
The circuit can be assembled on a Perf board.
Power supply Vs can be anything between 1.8V to 6V and it must be selected according to the rating s of the motor.
Maximum output current capacity of this circuit is 700mA.
TDA7274 must be mounted on a holder.
POT R3 can be used to vary the motor speed

Friday, October 10, 2014

Mini stereo circuit using ic TDA2822

This circuit IC1 TDA2822 number as your primary device. The Dual Amplifier IC or IC stereo gain at 40 dB. Bandwidth 120 kHZ. That is about 2 watts and watt power supply of 1.8 to 15 volts and a current 6 mA only
When using the power supply 9 volt into this circuit.VR1 and VR2 to adjust the signal level of the right and left, the pin 7 and pin 6 of IC1.The amplifier IC1 is out of the output pin 1 and pin 3, through the C4 and C5 coupling signals to the left and right speakers.The C6, R1 and C7, R2 is to reduce noise.

Friday, October 3, 2014

Electronic circuit uses a 555

The Electronic circuit uses a 555 timer wired as an astable oscillator and powered by the emitter current of the BC109C. Under dry conditions, the transistor will have no bias current and be fully off. As the probes get wet, a small current flows between base and emitter and the transistor switches on. A larger current flows in the collector electronic circuit enabling the 555 osillator to sound.

An On/Off switch is provided and remember to use a non-reactive metal for the probe contacts. Gold or silver plated contacts from an old relay may be used, however a cheap alternative is to wire alternate copper strips from a piece of veroboard.

These will eventually oxidize over but as very little current is flowing in the base circuit, the higher impedance caused by oxidization is not important. No base resistor is necessary as the transistor is in emitter follower, current limit being the impedance at the emitter (the oscillator circuit).

Thursday, October 2, 2014

Simple AC Line Circuit Using LED Indicator

The circuit in the figure illustrates to power a LED from the 120 volt AC line using a capacitor to drop the voltage and a small resistor to limit the inrush current. This circuit can operate one or two LED. There are three concept to operate the LEDs. Operation of this circuit is when the capacitor must pass current in both direction, a small diode is connected in parallel with the LED to provide a path for the negative half cycle and also to limit the reverse voltage across the LED. A second LED with the polarity reversed may be substituted for the diode, or a tri-color LED could be used which would appear orange with alternating current.

The circuit is fairly efficient and draws only about a half watt from the line. The resistor value (1K / half watt) was chosen to limit the worst case inrush current to about 150 mA which will drop to less than 30 mA in a millisecond as the capacitor charges. This appears to be a safe values, I have switched the circuit on and off many times without damage to the LED. The 0.47 uF capacitor has a reactance of 5600 ohms at 60 cycles so the LED current is about 20 mA half wave, or 10 mA averages. A larger capacitor will increase the current and a smaller one will reduce it. The capacitor must be a non-polarized type with a voltage rating of 200 volts or more.
The lower circuit is an example of obtaining a low regulated voltage from the AC line. The zener diode serves as a regulator and also provides a path for the negative half cycle current when it conducts in the forward direction. In this example the output voltage is about 5 volts and will provide over 30 milliamps with about 300 millivolts of ripple. Use caution when operating any circuits connected directly to the AC line.

Saturday, September 6, 2014

Digital DC Power supply using PWM with PIC microcontroller

In our lab I saw many DC power supply which have a variable knob to regulate the output. I was dreaming to make such a project where I can regulate the voltage using push button.As I am not an industrial level expert so this project is just about a digital DC power supply of small range(5V-12V). You can press push buttons to increase or decrease output voltage.Here we use LM317 to regulate the output voltage. Output voltage is controlled by the PWM output of a pic microcontroller.An OP-AMP is required to amplify the PWM output level. The idea is simple and easy to implement in schema.

Necessary Software:

1. Proteus 7.8 Professional
2. MicroC Pro
3. PICKIT 2.61 Boot Loader

Necessary Equipment:

1. PIC 16F73
2. LCD 16x2
3. 20 MHz Oscillator
4. Variable resistor (5k Ώ, 1k Ώ, 50k Ώ)
5. 7805 Voltage Regulator
6. 7818 Voltage Regulator
7. LM317T Voltage Regulator
8. LM741 Op Amp
9. Push Button Switch
10. Resistor (1k Ώ, 220Ώ)
11. Capacitor (47, 10, 1, 0.1 uF)
12. Vero board
13. Heat Sink

Methodology:

Figure1: Block Diagram of whole system

Schematic Diagram:

Figure 2: Schematic Diagram of the schema

Description:

· LM317 can give output of 3-37V . It can change its output voltage according to the adjust pin voltage.
· PWM signal is generated from microcontroller. The signal is applied to RC low pass filter which makes a DC voltage level.
· This voltage is applied to Op Amp to get required gain.
· This amplified voltage is applied to LM317 adjust pin.
· From microcontroller we adjust the width of PWM signal. More width gives higher DC level.
· It also changes the adjust pin voltage which controls the output of LM317.

Final Output:

Possible Application:

· Smooth speed control of DC motor

· Valve control of liquid and gas flow.
· Supply for different Electronic Circuit etc.

Downloads:

Download the full project file here.

Tuesday, September 2, 2014

FM transmitter using UPC1651

Here is the schema diagram of an FM transmitter using the IC UPC1651. UPC1651 is a wide band UHF Silicon MMIC amplifier. The IC has a broad frequency response to 1200MHz and power gain up to 19dB.The IC can be operated from 5V DC.

The audio signals picked by the microphone are fed to the input pin (pin2) of the IC via capacitor C1. C1 acts as a noise filter. The modulated FM signal will be available at the output pin (pin4) of the IC. Inductor L1 and capacitor C3 forms the necessary LC schema for creating the oscillations. Frequency of the transmitter can be varied by adjusting the capacitor C3.

Notes. * The schema can be assembled on a Vero board. * Inductor L1 can be made by making 5 turns of 26SWG enameled copper wire on a 4mm diameter plastic former. * A ¾ meter insulated copper wire can be used as the antenna. * Do not give more than 6V to the IC. * Mic M1 can be a condenser microphone.

Sunday, August 31, 2014

Metal Detector Circuit using 4011

I love the detector , this is actually one of my Hobbys, want to know more you saw the blog Metal Detector, there is lots of interesting information. But when we schema the principle of operation of this detector schema home metal consists of a mixture of two equal frequency causing interference. When one of the oscillators become unstable, the frequency of the interference is modified by changing the tone, so alert the user to the presence of a conductive metal near the coil.

Metal Detector cheap and easy to build

This detector is cheap and easy to build , requires neither a printed schema and can be tested directly over a breadboard . It is constructed using principal components as a transistor and a CMOS integrated schema 4011 .

The integrated schema 4011

The integrated schema 4011 consists of four NAND gates with two inputs each clock frequency depends on its supply voltage but reaches a maximum 10 MHz It operates in a recommended range of 3 V to 15 V supply range .

The operation of the Metal Detector

The oscillator is built with NAND gate N1 and a ceramic filter intermediate frequency ( IF) of 470kHz is used in this oscillator. The second oscillator was built with NAND gate N3 and an LC schema (coil + capacitor) . The frequency of the second oscillator is adjusted such that it will produce an audible oscillation frequencies of both , hence the name of this type of metal detector BFO ( Beat Frequency Oscillator ) .

The setting of this oscillator is done through the variable capacitor , you should adjust for parelhamento signals from two oscillators let the coil away from metals to prevent feedback . The signal from the second oscillator is amplified in the NAND gate N4 , mixed with the fixed oscillator in NAND gate N2 and amplified by the transistor again before going to the speaker .

If the sensor coil L1 get close to a metal object , this will modify the frequency of oscillation, causing the self - induction coil , unbalancing the frequency and consequently modifying the sound in the output. The metal detector coil L1, is made of 70 turns of enameled wire cover with diam . 0.3 to 0.6 mm and a diameter of 5 cm.

The Metal Detector

A metal detector is an electronic instrument that detects the presence of ferrous or non -ferrous metal nearby. Metal detectors are useful for finding metal objects hidden inside walls or buried in the soil . They usually consist of a portable unit with a sensing coil that can be swept on the ground or other objects .

If the coil approaches a metal piece will sound an alert indicated by a sound , an LED sign, or the oscillation of the galvanometer pointer . Typically, the device gives some indication of the distance when the metal is closest , which is a higher audio tone or higher level pointer.

Another common type of detectors are stationary detector. Metals are used for security screening at access points in prisons, banks, courts detectors, and airports, to detect metal weapons hidden in a persons body.

The first industrial metal detectors were developed in the 1960s and were widely used for mineral exploration and other industrial applications. Uses include de-mining (the detection of land mines), the detection of weapons such as knives and guns, geophysical prospecting, archeology and treasure hunting.

Metal detectors are also used to detect foreign bodies in food, and in the construction industry to detect steel reinforcing bars in concrete, tubes, pipes and wires buried in walls and floors.

Wednesday, August 27, 2014

Using 555 as FM transmitter Wiring diagram Schematic

The integrated schema 555 has no limits, this FM transmitter schema, the IC 555 is designed as an stable multivibrator as usual. But the tension control pin is used to connect a piezoelectric element instead of the capacitor disk. The piezoelectric element generates a voltage and the output pin is connected to an antenna wire 30 inches for the transmission of signals.Just tap the piezo element and you can hear the sound on an FM radio station. The range is very short.

Using 555 as FM transmitter Circuit Diagram

Tuesday, August 26, 2014

Calculation subwoofer using WinISD

In this article I want to talk about and show how you can calculate the subwoofer and what you should pay attention when designing in the following programs: WinISD 0.44, WinISD 0.50a7. Detailed description of the program WinISD .

Payment will be made for a box of ten-inch speaker Audiobahn 1051T. Lets start! Run the program WinISD 0.50a7

1. Create a new project (New Project).

2. By pressing this button, select the speaker of the database program.

3. View the T / S parameters.

4. T / S parameters. Click on (Next)

5. Selecting the number of speakers.

6. Type of installation.

Normal - all the speakers are on the same panel.

Isobaric speakers are face to face.

Click on (Next)

7. Efficiency speaker. Shows what type of housing is more suitable.

8. Selecting the type of box.

Sealed box - the name speaks for itself

Vented - box equipped with a pipe (Bass reflex).

Band pass 4th order - the speaker is located between the two chambers, one of which has a phase inverter.

Band pass 6th order - is between the two cameras equipped with both phase inverter.

Passive radiator - one closed box speaker and passive radiator (speaker without magnet)

Choosing which type suits us and click on (Next)

Next, the program offers a way to design the frequency response in different ways. I do not focus on this point and click Next.

If you select Passive Radiator enter the program will offer the following T / S parameters of the passive radiator:

Vas - is excited indoor air volume speaker.

Fs - resonant frequency.

Xmax - the maximum stroke of the diffuser.

QMS - Mechanical Q.

SD - diffuser area.

Next we consider the example program Band pass fourth order.

Tab Driver.

9-10. Again, you can specify the number and type of installation speakers.

11. Additional features.

Tab Box.

12-13. Camera box

14. Volume of the chamber.

15. The frequency of the camera settings.

Tab Vents (Phase inverter (s))

16. Number of bass reflex (s)

17. Fazoinvertor diameter (s)

18. Length bass reflex (s)

19. Type of round or rectangular. You can change the nav on a circle.

20. View fazoinvertora.

Turn to the main calculation box:

21. Click on the box shown schematically on the right mouse button while holding move the cursor along the axis (X) in-law to change the volume on the horizontal axis (Y) vertically to change the frequency. Similarly, the left mouse button to change the parameters of the lower chamber. The top of the curve should be above the red line between 35Hz and 120Hz if this subwoofer as widely as possible and smoother.

Transfer function magnitude. Amplitude frequency characteristic

Like this, but the lower limit of 40 Hz and the upper 113Gts is also suitable.

Where I marked with red dotted lines in practice there will be cut frequency crossover.

Select dates: Maximum Power.

Maximum Power

In this graph, the program shows the maximum power versus frequency. It can be seen that there is recession recession peak power 60 watts 39 hertz in practice cone speaker lacks stroke (Xmax) and an unpleasant sound - distortion. On the finished product it must also take into account and to limit the power

Select dates Maximum SPL

Maximum SPL. This chart shows the maximum sound pressure

Also seen a decline. For the same reason. Last two graphs from another speaker, I showed them to have clarity.

Here are graphs for our guinea. First a little far-fetched at a frequency of 0 Hz to 25 Hz and all the speakers there is a recession.

Now we must determine the size of the box will be installed speaker.

To do this, run the program WinISD 0.44 push a new project.

We need to introduce our dynamic parameters in this program because at its base it is not for this press «New»

We proceed to WinISD 0.50a7

22. By clicking this button you can see the T / S parameters that need to be put in WinISD 0.44.

Introduce the parameters and click OK to close the window so as not to interfere.

Create a new project.

23. Reposition the tick to select a speaker.

Press on, and do just as well as in WinISD 0.50a7

Transferring the parameters of the box in WinISD 0.50a7 WinISD 0.44.

24. Push to start to count the size of the box.

25. Press and the program provides the optimal dimensions in her opinion.

In disposal we have 10-inch speaker complete with its outer diameter of 300 mm to fit it into the box dimensions W and D Undue be less 300mm

26. Width 300mm inscribe equals 0,300 METERS

30. You can change the unit of measure by simply clicking on the dimension in this case the letter «m»

28. Length of 0,300 meters is entered

27. Push the «H» program shows height.

31. Pay attention to the L1 and L2 is the height of the cameras should look to tie the speaker depth does not exceed the value of L2.

But we must take into account the thickness of the material he is still in the lap of nutria has a shelf where the speaker stands and also take into account the thickness of the speaker himself, he, too, takes a beat him if I already priced big box in there to stand spacers they should also be taken into account. 7 parts obtained to calculate the correct items is necessary to consider that some of them will be unnecessarily whipped program shows the inner diameters. Letter «P» Ill puncture the material thickness which must be added to the other values.

1) D x W

2) D x W

3) D x W

4) H + (P * 3) x D

5) H + (P * 3) x D

6) H + (P * 3) x W + (P * 2)

7) H + (P * 3) x W + (P * 2)

Gets the size of the items if the material thickness of 20mm:

1) 300x300

2) 300x300

3) 300x300

4) 420h300

5) 420h300

6) 420h 340

7) 420h 340

Now we can proceed to the calculation of the phase inverter.

32. Type fazoinvertora we use a rectangular

33. Length. When the end of the phase inverter is shifted to the wall box

it virtually lengthened, and in fact it turns out that he is not listening on that frequency and greater long WinISD 0,44 ignores this virtual extension can be calculated by the formula itself but its easier to look in the program WinISD 0.55a7

I repeat: it is really only when the end of the phase inverter is shifted to the wall box and when he speaks it is not valid. So the program shows WinISD 0,44 28,86 cm and WinISD 0,55 25,64 a7 sm.F phase inverter will be installed in the item number 4 420h300 subtract 20 from 420 is the height fazoinvertora get exactly 400 square fazoinvertor unnecessarily adds another item 8) 300h255

Here are the final dimensions of parts and their number.

1) 300x300

2) 300x300

3) 300x300

4) 400x300

5) 420h300

6) 420h340

7) 420h340

8) 300h255

34. Air resistance. Air resistance in a vented enclosure to do as little as possible by increasing the opening area of the phase inverter.

Monday, August 25, 2014

Simple Water Sensor Wiring diagram Schematic using IC 555

This is a water sensor /rain alarm schema diagram; it can be used on motorcycle, car or other device that we want to protect from water, rain. This is a simple water sensor/rain alarm schema that makes an alarm when water/rain falls on its sensor. This schema is based on NE555/LM555 IC and two transistors (Q1&Q2). For transistor Q1- BC547 or BC107 and for Q2- 2N825,BC548 or BC168 can be used in the schema.

This rain detector schema can be supplied from voltage source of +9V-12V DC. The resistor 470K ohm is a POT/Variable resistor; it is used to adjust the sensitivity of water/rain sensor. Use a 8 ohm,0.5w-1W speaker to hearing better alarm. Less than 8 ohm speaker could be harmful for the IC 555.

Circuit Diagram of Water Sensor

We can make the water sensor as shown in the image (Fig-1) using aluminum conductor like a naked wire . Here can be used other conductor but we suggesting to use aluminum.

Supply Variable 1V to 9V Circuit using Power PC

This is a variable power supply which converts an input voltage from 12V SMPS / PSU a desktop computer, to an output voltage from 1.25 to 9 volts. This converter will be very useful for electronics hobbyists.

The schema uses a LM317T regulator IC that can reach up to 1 ampere, the diode D1 protects against polarity reversal and the diode D2 keeps the output voltage from the input voltage increases when an inductive or capacitive load is connected to the output.Similarly, the capacitor C3 removes any residual noise of the line regulates the voltage potentiometer VR1.

Supply Variable 1V to 9V using Power PC Circuit Diagram

Thursday, August 21, 2014

STEREO 75W 8Ω CLASS T DIGITAL AUDIO AMPLIFIER DRIVER USING DIGITAL POWER PROCESSINGTM TECHNOLOGY

GENERAL DESCRIPTION:

The TDA2075 is a two-channel, 75W (8Ω) per channel Amplifier Driver that uses Tripath’s proprietary Digital Power Processing (DPPTM) technology. The TDA2075 offers higher integration over previous Tripath amplifiers driver chipsets while providing exceptional audio performance for real world applications. Class-T amplifiers offer both the audio fidelity of Class-AB and the power efficiency of Class-D Amplifers.

Applications:

Powered DVD Players
Audio/Video Amplifiers & Receivers
Multimedia Speakers

Benefit:

Reduced system cost with smaller/less expensive power supply and heat sink
Signal fidelity equal to high quality
Class-AB amplifiers
High dynamic range compatible with digital media such as CD and DVD

Features:

Class-T architecture with proprietary DPP “Audiophile” Sound Quality
THD+N 0.015% at 50W, 8Ω, 1kHz
High Efficiency
91% at +/-40V and 120W, 8Ω
Supports wide range of output power levels
Up to 120W/channel (6Ω), single-ended outputs, @+/- 40V with 1% THD+N
Full Audio Bandwidth, 20Hz to 20kHz
Output over-current protection
Over- and under-voltage protection
Over-temperature protection
48-Pin LQFP Package
Complete Amplifier Evaluation Board available

Pinblok:

STEREO 75W (8Ω) CLASS-T DIGITAL AUDIO AMPLIFIER DRIVER USING DIGITAL POWER PROCESSINGTM TECHNOLOGY

Temperature Candle Using LED

LED based projects require a lot of skill and hence only experienced schema designers try out these diagram. But there are also a few diagram in this genre that can be done by amateur electronic hobbyists. The temperature candle is one such schema. Read on to know more about this.

The hardware components that are required to build this schema are listed below:

Microcontroller
Temperature Sensor
RGB LED
PCB

The schema design is pretty simple. The LED is made to flicker by the microcontroller and the color is based on the ambient temperature at that point. The temperature of the room can be known by observing the color of the LED.

The temperature value is obtained in degree Celsius. This value is received as a result of pressing the reset button on the PCB. This value can also be obtained by providing power to the device. Once the device is powered up, the change in temperature is indicated. The blue LED is triggered for a temperature increase of 10 degrees. The red LED is triggered for a temperature increase of a single degree.
Suppose, the ambient temperature is 23 degrees celsius, The schema works in such a way that the blue LED is made to blink twice and the red LED is made to blink 3 times. Soon after this, an orange colored flicker is observed as the LED goes into canfle mode.

Since through hole components are used in this schema, it is very cheap to construct and the components can be easily soldered. The schema also contains a jack for connecting to a Microchip Pickit 3 programmer / debugger. This reduces the complexity involved in code modification and download.