Showing posts with label circuit. Show all posts
Showing posts with label circuit. Show all posts

Saturday, January 11, 2014

Simple Power Switching Circuit Diagram

This Simple Power Switching Circuit Diagram provides on/off switching, soft starting, current monitoring, current tripping, and protection against over-current for a 30 Vdc power supply at normal load currents up to 2 A. The switch is turned on by an `on` command pulse; it is turned off by an `off` command pulse. An over-current trip can also be set on the bus side by a 6-digit binary signal, which is converted to an analog voltage and compared with the amplified voltage developed across a load-current-sensing resistor. 

Resistor/capacitor combinations (0.027 µ, 2 kfi) at the inputs of the current-sensing amplifiers act as low-pass filters: this introduces a few hundred /is of delay in the response to over-current, thereby providing some immunity to noise. The 0.022 µ capacitors connected to the drain terminals of the PFETs provide a Miller effect, which reduces the rate of change of the drain voltage and therefore the rate of rise of current at turn-on. The soft-turn-on time depends upon the load impedance and is typically 100 to 200 ms.

 Power Switching Circuit Diagram

Simple Power Switching Circuit Diagram

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Friday, January 10, 2014

Temperature Sensor Circuit Diagram

The LM35 temperature sensor provides an output of 10 mV/C for every degree Celsius over 0C. At 20C the output voltage is 20 10 = 200 mV. The circuit consumes 00. The load resistance should not be less than 5 kQ. A 4- to 20-V supply can be used.

Temperature Sensor Circuit Diagram

Temperature Sensor Circuit Diagram

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Thursday, January 9, 2014

Super linear FM Circuit Diagram

Designing various electronic circuit system (synthesizer, modem, decoder, data converter, etc) of ten need a frequency modulator subsystem. An FM modulator is very easy to build with TC9400 since the it has very good linearity as V/F converter. While Vin determines the amount of modulation (FM deviation) around the center frequency, the potentiometer determines the center frequency. Vin can be negative as well as positive.


Superlinear FM Circuit Diagram

Superlinear FM Circuit Diagram

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Wednesday, December 25, 2013

Sub Woofer and Controller Circuit Diagram

Sub woofers are popular, with home theater being of the driving forces. However, a nice sub adds considerably to normal hi-fi program material, & so if it is predictable & has nice response characteristics.

 all of sub woofers use a immense speaker driver in a immense box, with tuning vents & all the difficulties (& vagaries) that conventional operation entails. By conventional, I mean that the speaker & cabinet are operated as a resonant technique, using the Thistle-Small parameters to get a box which will (if everything works as it ought to) provide excellent performance.

Completed Prototype


Completed Prototype

A fast word is warranted here, to let you decide if the speaker you have will actually work in a little sealed enclosure. The EAS principle will permit any driver to extend to twenty Hz or even lower. A lovely fast check is to stick the speaker in a box, and drive it to 100W or so at twenty Hz - you ought to see lots of cone movement, a few things will rattle, but you should not actually listen to a tone. A "bad" speaker will generate 60 Hz (third harmonic) - in the event you dont listen to anything, the speaker will work in an equalized sub.

If a tone is audible, or the speaker shows any signs of distress (such as the cone breaking up with appropriate terrible noises), then the driver cannot be used in this manner. Either discover a different driver, or use a vented enclosure.

Before you can build your own EAS box, you will require to pick an appropriate driver, using the above as a guide. Cone tour will be high at the lowest frequencies, so the speaker needs to be able to high power, lovely tour, & of reasonable size (there is no substitute for cone area for moving air at low frequencies). I am using a 380mm (15") driver, but smaller drivers (say 300mm - 12") can be used, or even a bigger number of smaller drivers. I have also had excellent results with a single 300mm driver, which has lower sensitivity (as would expect) but is perfectly adequate for normal usage.


The check methods I used are applicable to any combination, but in general I recommend either a single giant driver or a pair of (say) 300mm units. The next hurdle is the amplifier needed to drive the speaker. This is not trivial. If the selected driver has a sensitivity of 93dB / W @ one metre, then you can safely assume that the efficiency will be less than this below resonance, by a factor of possibly 6dB or more. In case you are used to driving a sub with 100W, this means that you have increased the power to 400W - although this is an over-simplification.

If they are to operate the sub from 60Hz (my aim from the outset), they will increase the power by 12dB for each octave, so if 20W is necessary at 60Hz, then at 30Hz this has increased to 320W, & at 15Hz, you will require over 5kW.

Fortunately, the reality is a tiny different, & 400W or so will be over sufficient for a powerful process, due chiefly to the fact that the energy content in the low bass region is not normally all that great. (Although some program material may have high energy content, in general this is not the case). The EAS process augments the existing process, which is allowed to roll off naturally - contrast this with the normal case, where a crossover is used to separate the low bass from the main process, so existing speaker capability is lost.

The box I built is made from 25mm (1") MDF (Medium Density Fiberboard), & filled with fiberglass. Apart from the fact that it is very heavy (which is a lovely thing, because it desires to walk with low frequencies), the cabinet is acoustically dead, with no resonances in the low frequencies at all ( unlike my house & furniture, dammit !). The woofer is recessed in to the baffle, & sealed with weather sealing foam. When attaching the speaker, do NOT use wood screws, or any other screw in to the MDF. I used "Tee" nuts. I have no idea what they are called elsewhere in the world, but they look like this

TEE NUT

The middle is tapped, and accepts a metal thread screw, and the small spikes mean that you must drill a hole, and hammer in the Tee nut. In case you use a screw through the hole and screwed lightly in to the Tee nut, you can hold it in place as you bash away at it, and can also see that it is straight when you are done. make sure that the finish of the screw doesnt stick out the finish, or you will seldom remove it again after the hammering! I recommend that you lock the tee nut in to place with some construction adhesive (dont get any in the threaded section) so they dont fall out while you are installing the speaker.

The EAS Controller
The controller is (actually very) simple, & the circuit is shown in Figure one. An input buffer ensures that the input impedance of the source does not affect the integrator performance, & allows summing of left & right channels without any crosstalk. The output provides a phase reversal switch, so that the sub can be properly phased to the remainder of the process. If the mid-bass disappears as you advance the level control, then the phase is wrong, so switch to the opposite position.

Figure 1 - The Original EAS Filter / Controller

It turns out that the controller can be simplified, but there is no point. While the dual pot appeared like a lovely suggestion when I built my unit, it actually only changes the gain. Now, having experimented some more, this is an excellent thing, since it means that the level through the controller can be set to make positive that there is no distortion - there can be a immense amount of gain at low frequencies, & if the gain is high, distortion is assured!

The integrators (U1B & U2A) include shelving resistors (R6 & R9), & the capacitor / resistor networks (C1-R4, C3-R7) be positive that signals below 20Hz are attenuated. In case you dont require to go that low, then the worth of the caps (or the resistors R4 & R7) can be reduced. I used four.7uF caps, & these are non-polarized electrolytic - a high value was needed to keep the impedance low to the integrators. I originally included the dual pot (VR1) to permit the upper frequency roll off to be set - however it does no such thing (as described above). The final output level is set with VR2, which may be left out if your power amp has a level control.

It is OK to substitute different op amps, but there is tiny reason to do so. Any substitution tool ought to be a FET input op amp, or DC offset may be an issue. Do not be tempted to make use of a DC coupled amp. If the you are planning to make use of is DC coupled, the input ought to be isolated with a capacitor. Pick a value to give a -3dB frequency of about 10Hz, as this will have tiny effect on the low frequency response, but will help to attenuate the subsonic frequencies.

The unity gain range (using a 20k pot as shown) is from 53Hz to 159Hz. This ought to be sufficient for most systems, but if desired, the resistors (R5 & R8) can be increased in value to 22k, or you can select a bigger value pot. Using 22k resistors & the 20k pot will give a range from 36Hz to 72Hz.

To permit lower frequencies, you can increase the 100k shelving resistors (R6 and R9) to 220k, and increase the high pass capacitors (four.7uF) with 10uF (or R4 & R7 may be increased - a maximum of four.7k is recommended). This will give a turnover frequency of around 8Hz, but expect to make use of much more power, as there will likely be significant sub-sonic energy that will generate huge cone excursions with no audible benefit.

The input must be a standard full range (or for a stampeded method, the whole low frequency signal). Do not use a crossover or other filter before the EAS controller. For final modification, and to integrate the method in to your listening room, I recommend the constant-Q equalizer. The final result using this is extraordinarily nice - I have flat in-room response to 20Hz!

For the power supply, use the in anything else will provide +/-15V at a few Milli amps. My supply is not even regulated, & the whole method is as close to noiseless as you will listen to (or not listen to). Construction is not critical - I built mine on a piece of Overboard (perforated prototype board), & managed to fit everything (including the power supply rectifier & filter) on a piece about 100 x 40 millimeters with room to spare.

The EAS method is surprisingly simple to set up with no instrumentation. Of coursework in case you have an SPL meter & oscillator you can also confirm the settings with measurements. Keep in mind that the room acoustics will play havoc with the results, so unless you require to drag the whole method outside, setting by ear might be the simplest. Even in case you did get it exactly right in an anechoic surroundings, this would alter one time it was in your listening room anyway.

It takes a small experimentation to get right, but is surprisingly simple to do. When properly set, a check track (or bass guitar) ought to be smooth from the highest bass note to the lowest, with no gross peaks or dips. Some are inevitable because of room resonances & the like, but you will discover a setting that sounds "right" with small difficulty.

Performance Of My Prototype
I measured 80dB SPL at one meter in my workshop (sub-woofer perched on a chair in more or less the middle of the space) with at 25Hz & 70W. This improved dramatically when the unit was installed in the listening room, but as I said earlier, there is usually not a lot recorded below around 35Hz. The longest pipe on the organ is usually about 16Hz, but larger pipes still may be used. It was found necessary to cease group of diapasons (able to 8Hz) in the famous Sydney Town Hall organ because when they were used, the very low frequency caused building destroy.

A couple of orchestral recordings revealed traffic (or perhaps underground railway) rumble that I was unaware of before (however this was before it was set correctly, and the bass was a tad louder than needed). One time set up properly, its presence is unobtrusive - except I now have about and a half octaves of additional bottom finish.

I finally decided on a 20Hz maximum frequency (-3dB), and this is reflected in the part values shown in Figure one. The actual roll-over frequency is 16.5Hz, after which the output is attenuated at about 12dB / octave (see Figure two). Without the roll off capacitors, the gain would be 20dB at 20Hz. Unity gain frequencies are about 4Hz and 63Hz with the 20k pot(s) centered.

Figure 2 - Frequency Response of EAS Controller

awesome Australian readers may recognize the woofer brand in the picture (Figure three) of my done unit. The compact size of the box can be seen from the fact that there is tiny spacing around the speaker itself, and most of what is there is the top and sides - I used 25mm MDF, so it makes the outside of the box a bit bigger than the inside. Outside dimensions are 470W x 450H x 410D (18 1/2"W x 17 1/2"H x 16"D), which gives a capacity of 60 liters (about two.1 ft³ - excluding the internal space occupied by the speaker. I think you would agree that this is a small box indeed for a 380mm loudspeaker that performs down to 15Hz.

Figure 3 - Photo of Completed EAS Cabinet


Overall, I would must say that I doubt that any conventional design would be as compact, or would have such clarity & solidarity. Being a sealed box, there is not of the "waffle" that ported designs often give, & the speaker is protected against excessive tour by the air pressure in the box itself (below the cutoff frequency, anyway).

The bottom finish in my technique is now staggering. It is rock solid, & absolutely thunders when called on. The 400W amp is over sufficient for the job, thinking about its to keep up with a biamped main technique able to high SPL (up to 120dB at my listening position). In fact a fast check indicates that 200W would have been (but . better to have it & not require it than require it & not have it).

The fact that the EAS design augments the existing speakers than taking over from them with a crossover goes a long way towards ensuring the power requirements do not get out of hand. As an added benefit, I have found that I get the same aural sensation at much lower SPLs - I can listen happily at 90dB, but it sounds much louder. I may even listen to the phone ring while listening now !
All in all, I feel it is unlikely that anything other than an isobaric enclosure could give the same performance for a box size even close to the EAS box,& even then would be limited to about 35Hz. Added to this is the unpredictable combined response of the main speakers and the sub, which is not an Problem with this design. With an EAS system, more power is necessary than a standard design, but for plenty of people, power is less costly than space.
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Tuesday, December 24, 2013

Simple Solar Cell Voltage Regulator Circuit Diagram

This is a Simple Solar Cell Voltage Regulator Circuit Diagram. This device is designed to be a simple, inexpensive ‘comparator’, intended for use in a solar cell power supply setup where a quick ‘too low’ or ‘just right’ voltage indicator is needed. The circuit consists only of one 5V regulator, two transistors, two LEDs, five resistors, two capacitors, and one small battery. Although a 4-V battery is indicated, 4.5 V (3 alkalines in series) or 3.6 V (3 NiCd cells in series) will also work. 

 Solar Cell Voltage Regulator Circuit Diagram

 Solar Cell Voltage Regulator Circuit Diagram

The specifications of voltage regulator IC1 are mainly determined by the size and number of the solar cells and the current pull of the equipment connected to the output. Here the low-drop 4805 is suggested but other regulators may work equally well as long as you observe the output voltage of the solar cells. Transistors T1 and T2 are complementary types i.e. one each of the pnp and npn variety. 

Although the ubiquitous BC557B (pnp) and BC547B (npn) are indicated, any small-signal equivalents out of the junk box will probably do. The values of voltage dividers R1/R6 and R3/R4 may need to be adjusted according to the type of transistor and its gain, or according to the desired voltage thresholds. Using the resistor values shown in the schematic, LED D2 turns on fully when the voltage is just above 5 volts. 

LED D1 turns on when the voltage drops below 4.2 volts or so. Between those two thresholds, there is a sort of no man’s land where both LEDs are on dimly. A buzzer or other warning device could be connected across the terminals of LED D1 to give a more substantial warning if the voltage drops below operating limits. The current consumption of the circuit is about 20 mA at 5 V, and it decreases with the voltage supplied by the solar cells.

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Tuesday, October 8, 2013

VW CAR PASSAT ENGINE CONTROL AND AUTOMATIC SOLENOID ELECTRICAL WIRING CIRCUIT


VW CAR PASSAT ENGINE CONTROL AND AUTOMATIC SOLENOID ELECTRICAL WIRING CIRCUIT

1993 VW Passat Engine Control Module, Automatic Control Unit, and Automatic Solenoid Electrical Wiring Diagram are shown in the following figure. It shows the connection and wiring between each parts and component of Engine Control Module, Automatic Control Unit, and Automatic Solenoid system of the vehicle such as the multi-function switch, fuse/relay panel, knock sensor, coolant temperature sensor, shift lock solenoid, starter interlock/back up lit relay,automatic control computer clutch shut off relay, automatic control unit, automatic solenoids, program switch, throttle position sensor, full throttle switch, idle switch, throttle valve potentiometer, ignition booster, distributor firing order, engine control module, carbon canister, cold starter, idle air control valve, evap emission on/off valve, and many more.
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Saturday, September 28, 2013

The Gentle Touch Circuit Diagram

Consumer appliances these days hardly ever have a proper mains switch. Instead, appliances are turned on and off at the touch of a button on the remote control, just like any other function. This circuit shows how a device (as long as it does not draw too high a current) can be switched on and off using a pushbutton. The approach requires that a microcontroller is already available in the circuit, and a spare input port pin and a spare output port pin are required, along with a little software. When power is applied T1 initially remains turned off. When the button is pressed the gate of T1 is taken to ground and the p-channel power MOSFET conducts. The microcontroller circuit is now supplied with power. Within a short period the microcontroller must take output PB1 high. This turns on n-channel MOSFET T1 which in turn keeps T1 turned on after the push-button is released.

Now the microcontroller must poll the state of the push-button on its input port (PB0) at regular intervals. Immediately after switch-on it will detect that the button is pressed (a low level on the input port pin), and it must wait for the button to be released. When the button is next pressed the device must switch itself of f: to do this the firmware running in the microcontroller must set the output port pin to a low level. When the button is subsequently released T1 will now turn off and the supply voltage will be removed from the circuit.

The circuit itself draws no current in the off state, and for (rechargeable) battery-powered appliances it is therefore best to put the switch before the voltage regulator. For mains-powered devices the switch can also be fitted before the voltage regulator (after the rectifier and smoothing capacitor). Since there is no mains switch there will still be a small standby current draw in this case due to the transformer. Be careful not to exceed the maximum gate-source voltage specification for T1: the IRFD9024 device suggested can withstand up to 20 V. At lower voltages R2 can be replaced by a wire link; otherwise suitable values for the voltage divider formed by R1 and R2 must be selected.

Circuit diagram:

the-gentle-touch-circuit-diagramw The Gentle Touch Circuit Diagram

The author has set up a small website for this project at http://reweb.fh-weingarten.de/elektor, which gives source code examples (which include dealing with pushbutton contact bounce) for AVR microcontrollers suitable for use with AVR Studio and GNU C. Downloads are also available at http://www.elektor.com.

Rainer Reusch - Elektor Electronics 2008

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Wednesday, September 11, 2013

4A High Speed Low Side Gate Driver Circuit

 The UCC27518 and UCC27519 single-channel, high-speed, low-side gate driver device is capable of effectively driving MOSFET and IGBT power switches. Using a design that inherently minimizes shoot-through current, UCC27518 and UCC27519 are capable of sourcing and sinking high, peak-current pulses into capacitive loads offering rail-to-rail drive capability and extremely small propagation delay typically 17 ns.

  4A High-Speed Low-Side Gate Driver Circuit

 4A High-Speed Low-Side Gate Driver Circuit


 The UCC27518 and UCC27519 provide 4-A source, 4-A sink (symmetrical drive) peak-drive current capability at VDD = 12 V. The UCC27518 and UCC27519 are designed to operate over a wide VDD range of 4.5 V to 18 V and wide temperature range of -40°C to 140°C. Internal Under Voltage Lockout (UVLO) circuitry on VDD pin holds output low outside VDD operating range.


Features
  • Low-Cost, Gate-Driver Device Offering Superior Replacement of NPN and PNP Discrete Solutions
  • Pin-to-Pin Compatible With TI’s TPS2828 and the TPS2829
  • 4-A Peak Source and 4-A Peak Sink Symmetrical Drive
  • Fast Propagation Delays (17-ns typical)
  • Fast Rise and Fall Times (8-ns and 7-ns typical)
  • 4.5-V to 18-V Single Supply Range
  • Outputs Held Low During VDD UVLO (ensures glitch free operation at power-up and power-down)
  • CMOS Input Logic Threshold (function of supply voltage with hysteresis)
  • Hysteretic Logic Thresholds for High Noise Immunity
  • EN Pin for Enable Function (allowed to be no connect)
  • Output Held Low when Input Pins are Floating
  • Input Pin Absolute Maximum Voltage Levels Not Restricted by VDD Pin Bias Supply Voltage
  • Operating Temperature Range of -40°C to 140°C
  • 5-Pin DBV Package (SOT-23)
Device Uses
  • Switch-Mode Power Supplies
  • DC-to-DC Converters
  • Companion Gate Driver Devices for Digital Power Controllers
  • Solar Power, Motor Control, UPS
  • Gate Driver for Emerging Wide Band-Gap Power Devices (such as GaN)
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Saturday, August 31, 2013

Pulse Timer Control Relay Circuit with IC555

Today we would like to offers solutions for a set time for take control relay and take NO. / NC. contact to apply to control other devices . such as disable or enable the device.function of this circuit is using IC555 to determine the pulse and a resistor R1 to the period of time.

Pulse Timer Control Relay Circuit Diagram


Pulse Timer Control Relay Circuit with IC555

R1       #Seconds
100k         2
220k         3
470k         6
1M           15

The increase provides more time to increase the value of the Capacitor.

Part List
R1 = 1 Meg, Preset Pot
R2 = 10K  
R3,R4 = 1K
C1 = 10uF, 16V
C2 = 0.01uF
T1 = BC547 (Gen Purp NPN)
T2 = 2N2222 (Hi Current NPN)
D1 = 1N4001 (Gen Purp Si)
IC1 = 555 (Lo-Power version)
RLA1 = Relay, 9V (amps of your choice)
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Sunday, August 11, 2013

Power Mosfet Inverter Circuit Diagram

This Power Mosfet Inverter Circuit Diagram can deliver .high-voltage ac or dc, with a rectifier and filter, up to several hundred volts. The secondary and primary of T1-a 12.6 to 440 V power transformer, respectively-are reversed; e.g., the primary becomes the secondary and the secondary becomes the primary. Transistors Q1 and Q2 can be any power FET. Be sure to heat sink Q1 and Q2. Capacitors C1 and C2 are used as spike suppressors. 

 Power Mosfet Inverter Circuit Diagram


Power Mosfet Inverter Circuit Diagram
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Saturday, August 10, 2013

3000W Stereo Power Amplifier Circuit


Circuit Power Amplifier has a power output of up to 1500W RMS power amplifier circuit is often used to power sound systems keperlun for outdor. In the final image can be seen a series of power amplifiers using 10 sets of power transistors for the ending.

This power amplifier circuit using a transistor amplifier from the front, signal splitter, driver and power amplifier. Current consumption required is quite large power amplifier that is 15-20 A 1500W power amplifier circuits for this. Supply voltage needed by the power of this amplifier is the optimal working order symmetrical 130VDC (130VDC-130VDC ground). 1500W amplifier circuit below is a picture series of mono, stereo if you want to make it necessary to make two copies of the circuit. For more details can be viewed directly image the following 1500W power amplifier circuit.

The series of High Power Amplifier 1500W With Transistor
Click Image to view larger


In the above series of power amplifer 1500W is equipped to control a DC Offset function to set the power amplifier is turned on at the moment and with no input signal then the output should be 0VDC. Then also equipped with a flow regulator to the power amplifier bias. Final part of this power amplifier requires adequate cooling to absorb the heat generated. Power amplifier is not equipped with a speaker protector, therefore it is necessary diapsang protector on the speaker output so that when the power amplifier is not the case turned on the beat to the speaker that can damage the speaker.
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Tuesday, August 6, 2013

Cell Phone Jammer Circuit Diagram

Circuit showing a mobile phone jammer. A beautiful diy gsm jammer or mobile cell phone jammer schematic diagram for use only in GSM1900 with frequency from 1930 MHz to 1990 MHz. The GSM1900 mobile phone network is used by USA, Canada and most of the countries in South America.

This cell phone jammer is not applicable for use in Europe, Middle East, nor Asia. The GSM jammer circuit could block mobile phone signals which works on GSM1900 band, also called DCS. For more cell phone jammers check the related posts.

Cell Phone Jammer Circuit Diagram

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Sunday, August 4, 2013

Transformerless Power Supply Circuit

This circuit will supply up to about 20ma at 12 volts. It uses capacitive reactance instead of resistance; and it doesnt generate very much heat.The circuit draws about 30ma AC. Always use a fuse and/or a fusible resistor to be on the safe side. The values given are only a guide. There should be more than enough power available for timers, light operated switches, temperature controllers etc, provided that you use an optical isolator as your circuits output device. (E.g. MOC 3010/3020) If a relay is unavoidable, use one with a mains voltage coil and switch the coil using the optical isolator.C1 should be of the suppressor type; made to be connected directly across the incoming Mains Supply.
They are generally covered with the logos of several different Safety Standards Authorities. If you need more current, use a larger value capacitor; or put two in parallel; but be careful of what you are doing to the Watts. The low voltage AC is supplied by ZD1 and ZD2. The bridge rectifier can be any of the small Round, In-line, or DIL types; or you could use four separate diodes. If you want to, you can replace R2 and ZD3 with a 78 Series regulator. The full sized ones will work; but if space is tight, there are some small 100ma versions available in TO 92 type cases. They look like a BC 547. It is also worth noting that many small circuits will work with an unregulated supply.
Circuit diagram:
Transformerless_Power_Supply_Circuit Diagram
Transformerless Power Supply Circuit Diagram
You can, of course, alter any or all of the Zenner diodes in order to produce a different output voltage. As for the mains voltage, the suggestion regarding the 110v version is just that, a suggestion. I havent built it, so be prepared to experiment a little. I get a lot of emails asking if this power supply can be modified to provide currents of anything up to 50 amps. It cannot. The circuit was designed to provide a cheap compact power supply for Cmos logic circuits that require only a few milliamps. The logic circuits were then used to control mains equipment (fans, lights, heaters etc.) through an optically isolated triac.
If more than 20mA is required it is possible to increase C1 to 0.68uF or 1uF and thus obtain a current of up to about 40mA. But suppressor type capacitors are relatively big and more expensive than regular capacitors; and increasing the current means that higher wattage resistors and zener diodes are required. If you try to produce more than about 40mA the circuit will no longer be cheap and compact, and it simply makes more sense to use a transformer. The Transformerless Power Supply Support Material provides a complete circuit description including all the calculations.
Web-masters Note:
I have had several requests for a power supply project without using a power supply. This can save the expense of buying a transformer, but presents potentially lethal voltages at the output terminals. Under no circumstances should a beginner attempt to build such a project.
Important Notice:
Electric Shock Hazard. In the UK,the neutral wire is connected to earth at the power station. If you touch the "Live" wire, then depending on how well earthed you are, you form a conductive path between Live and Neutral. DO NOT TOUCH the output of this power supply. Whilst the output of this circuit sits innocently at 12V with respect to (wrt) the other terminal, it is also 12V above earth potential. Should a component fail then either terminal will become a potential shock hazard.
MAINS ELECTRICITY IS VERY DANGEROUS.
If you are not experienced in dealing with it, then leave this project alone. Although Mains equipment can itself consume a lot of current, the circuits we build to control it, usually only require a few milliamps. Yet the low voltage power supply is frequently the largest part of the construction and a sizeable portion of the cost.
Author: Ron J - Copyright: Zen
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Saturday, August 3, 2013

Telephone Line Monitor Circuit

This is a circuit that will find application in the case where you have a lot of telephones installed on a telephone line and would want to know if somebody of them is open. Thus you will not be off any discussion. Simultaneously it can cut the certain sound from stereo amplifier that are in high volume, the sound of some television or turn on some light the night when it ring the telephone and needs him you raise. Here’s the figure of the circuit;


Exists a pair of free contacts of RL1 that connects to the J2, which you can use connecting there any appliance you want. The telephone line connected in the J1, with what polarity you wants. When the telephone is closed then the line voltage is roughly, 48-50Vdc. This voltage turn on the photo diode and this, the transistor of IC1, which it simultaneously isolates, the circuit from the telephone line. The photo transistor in IC1 are now in situation ON, the input of IC2A are LOW [L] and output HIGH [H]. Ignoring for little the circuit of delay D6, R4, R5, C1, the IC2B input, are also this HIGH hence the output are LOW, transistor Q1 are OFF and the RL1 are deactivate. When the telephone earphone is raised, then the telephone voltage line fall in 6-10Vdc.

All the previous situation is reversed also the RL1, turn on. The telephones that use for dial choice, disk or pulse system, can they open and close the RL1 at the duration of choice. With delay network, that exist between in gates IC2A and in the IC2B, we delay the situation changes in the input of IC2B, ensuring thus stability in the operation of RL1. If the R4=100K then the RL1 is activated when the telephone ring or when the earphone is raised. On the contrary if the R4=1M, then the RL1 is activated only when the earphone is raised. The circuit supply becomes with a simple regulation circuit, in + 12V.

Part:

R1-2=36Kohm
R3=100Kohm
R4=100Kohm or 1Mohm 
R5=2.2Mohm
R6=3.3Kohm
R7=1Kohm
D1....4=1N4002
D5=1N5252 [24V 0.5W Zener]
D6-7=1N4148
D8....11=1N4002
D12=Red Led 3 or 5mm
RL1=12Vdc 2X2 relay
J1-4=2pin connector 2.54mm step
J2=6pin connector 5mm step
J3=2pin connector 5mm step
F1=Fuse 500mA [5x20mm]
C1=100 or 220nF 100V MKT
C2=1000uF 25V
C3-4=100nF 100V
C5=4.7uF 16V
IC1=4N25 opto coupler
IC2=4011B
IC3=7812 [1A]
Q1=BD139 or BD679
T1=12Vac 500ma tranformer for pcb
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Thursday, August 1, 2013

Battery Powered High voltage Generator Circuit Diagram

This is the battery powered high-voltage generator circuit diagram. Output voltage great enough to jump a l-inch gap can be obtained from a 12-V power source. A 555 timer IC is connected as an stable multi vibrator that produces a narrow negative pulse at pin 3. The pulse turns Ql on for the duration of the time period. The collector of Ql is direct-coupled to tbe base of tbe power transistor Q2, turning it on during the same time period. 

The emitter of Q2 is direct -coupled through current limiting resistor R5 to the base of the power transistor. Q3 switches on, producing a minimum resistance between the collector and emitter. The high-current pulse going through tbe primary of high-voltage transformer Tl generates a very high pulse voltage at its secondary output terminal (labeled X). The pulse frequency is determined by tbe values of Rl, R2, and C2. The values given in the parts list were chosen to give the best possible performance when an auto-ignition coil is used for Tl. 

Battery Powered High-voltage Generator Circuit Diagram

Battery Powered High-voltage Generator Circuit Diagram
 
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Monday, July 29, 2013

Antialiasing And Sync Compensation Filter Circuit Diagram

Antialiasing And Sync-Compensation Filter Circuit Diagram. Two dual-bi-quad filter chips and some external components form a multipurpose filter to reconstruct D/A converter signals. Connected to a converter`s output, the filter provides anti-aliasing, reduces the D/A converter`s quantization noise, and compensates for sin(7rx)()—the `sync` function (attenuation). The circuit incorporates an inverse-sync function that operates to one-third of the converter`s sample rate. Beyond one-third, the filter`s response shifts to a stop band filter, which provides -70 dB attenuation. 

This attenuation conforms to the converter`s inherent signal-to-noise ratio and quantization error. To prevent aliasing, the stop band edge must be no higher than the Nyquist frequency (/„ + 2). To achieve 70-dB stop band rejection with this eighth-order filter requires a transition ratio (/stop band -K/pass band) of 1.5, which sets the passband`s upper limit at fs +3. Notice also that you can apply a simple divide-by-64 circuit to the 192-kHz clock frequency to set the necessary 3 ratio between the converter`s sample rate and the filter`s 1-kHz corner frequency. 

Antialiasing And Sync-Compensation Filter  Circuit Diagram

Antialiasing And Sync-Compensation Filter  Circuit Diagram
 
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Wednesday, June 12, 2013

TDA1562Q 36 Watt Audio Power Amplifier circuit and explanation

36 Watt Audio Power Amplifier Circuit Using TDA1562Q

Its based on a Philips class-H audio amplifier IC and can deliver 36W RMS OR 70W music power, all from a 13.8V supply. Our new Mighty Midget Amplifier can really pack a punch - around 36W RMS continuous into a 4-ohm load when using a 13.8V supply. However, its the 70W of output power that it can deliver during dynamic (music) signal conditions that really make you sit up and take notice.

Picture of 36 Watt Audio Power Amplifier Using TDA1562Q

As can be seen from the photos and the circuit diagram, the Mighty Midget uses just a handful of parts. Its built on a PC board that measures just 104mm x 39mm but while its size may be modest, theses nothing at all modest about its power output. And the noise and distortion figures are pretty good too.

Circuit diagram:

36 Watt Audio Power Amplifier Circuit Diagram

At the heart of the circuit is the TDA1562Q IC, described by Philips as a "monolithic integrated Bridge-Tied Load (BTL) class-H high-efficiency power amplifier". It comes in a 17-pin "DIL-bent-SIL" plastic package and is not only designed for use in car audio and portable PA work but for mains applications as well; eg, mini/midi audio components and TV sound.

Parts layout:

Parts Layout Of 36 Watt Audio Power Amplifier

PCB layout:

PCB Layout Of 36 Watt Audio Power Amplifier

Performance:

Output power:----------------------36W RMS into 4R
Music power:-----------------------70W into 4R
Frequency response:---------------1dB down at 28Hz and 55kHz
Input sensitivity:-------------------130mV RMS (for 36W into 4?)
Harmonic distortion:----------------typically 0.2% (see graphs)
Signal-to-noise ratio:----------------95dB unweighted (22Hz to 22kHz)
Source: Silicon Chip March 2002
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Sunday, May 26, 2013

Three sirens in one Circuit

This is a siren circuit diagram Here I have used UM3561 circuit diagram.This circuit can be operated with 3V.It can generate 3 sirens.Here I have used IC 2SC9013 you can use the same IC or similar IC. Use 8ohm 0.2W speaker.


Note:-

* Dont use more than 3V
* Dont use this for unnecessary things
* Build this circuit on a PCB
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Saturday, April 13, 2013

Simple 500W Audio Power Amplifier Circuit Diagram with Transistor

We take transistor MJL2194 and MJL2193 for pressure output signal.so the amp has a capability for enormous instantaneous current potential.

Simple 500W Audio Power Amplifier Circuit Diagram with Transistor

Circuit Functional
I use the -85 volt when the output current is supplied to the drive 350 to 340 very hot. Increase the output present, but it was once too chilly. The output to warmth up sooner than a regular open it. Sounds evident, but sound high quality is somewhat excellent.

I recomment it by way of turning out for the evening. If the force is installed on the steel part out.

I assume simple. View full above, the statement that R 30 ohm then the voltage throughout the 0.86 V exhibit that the brand new via its 29 mA for those who add a file to / – eighty five V, and think that the voltage throughout the part physique. It was the identical in each the R 30 ohm to get an awfully light 5 zero.86 = 5.86 V and the present I can be 5.86/30 = zero.195 A = 195 mA, and the specification of mje340. mje350 get Ic (max) = 500 mA, so it is pure for it to heat up. Actually, it isn't essential to adhere to sync tr output must be interested in the following two tr power force is healthier. For VR will have to be R300 .


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Tuesday, April 9, 2013

A Homemade Fence Charger Energizer Circuit Explained

The electric fence charger circuit presented here is basically a high voltage pulse generator. The super high voltage is derived from a commonly used automobile ignition coil. An astable multivibrator is used to generate the required frequency to drive the ignition coil. Another astable is used to control the pulses supplied to the fence.






If you have large agricultural fields and desperately need to protect the crops from uninvited guests like animals and possibly humans, then this electric fence charger device is just what you are looking for. Build and install it yourself.


An electric fence is an electrified high voltage barrier which produces painful shocks if physically touched or manipulated. Thus such fencing basically function as deterrents for animals as well as human intruders and stop them from crossing the restricted boundary.

The present circuit of an electric fence charger is designed and tested by me and has proved sufficiently powerful for the application. 

The circuit is able to produce voltage pulses up to 20,000 volts, needless to say about the fatality rate involved with it. However the pulses being intermittent, provides the subject with enough time to realize, recover and eject.

The generated pulse is so powerful that it can easily arc and fly-off between short distances of around a cm. so the fencing conductor needs to be separated adequately to avoid leakages through arcing and sparking. If not tackled, may drastically reduce the effectiveness of the unit.

Here the generation of high voltage is primarily carried out by an automobile ignition coil. 

The winding ratios of an ignition coil are specifically designed and intended for creating high voltage arc between a two closely spaced conductors inside the ignition chamber to initiate the ignition process in vehicles.

Basically it’s just a step-up transformer, which is able to step-up an input applied voltage at its primary winding to monstrous levels at its output or the secondary winding.

SOME POINTS OF THE CIRCUIT AND THE IGNITION COIL IS VERY DANGEROUS TO TOUCH WHEN POWERED. ESPECIALLY THE IGNITION COIL OUTPUT IS TOO LETHAL AND MAY EVEN CAUSE PARALYSIS.







Let’s diagnose the whole thing more deeply.

 Circuit Description


In the CIRCUIT DIAGRAM we see that the entire circuit is basically comprised of four stages.
A DC oscillator stage,

An intermediate 12 to 230 volts step-up stage,

The voltage collector and firing stage and
The super high voltage-booster stage.

 TR1 and TR2 are two normal step-down transformers whose secondary windings are connected through SCR2. TR2’s input primary winding may be selected as per the country specification.

However, TR1’s primary should be rated at 230 volts.

IC1 along with the associated components forms a normal astable multivibrator stage. The supply voltage to the circuit is derived from the secondary of TR2 itself.

The output from the astable is used to trigger SCR2 and the whole system, at a particular fixed intermittent rate as per the settings of P1.

During the ON periods, SCR2 connects the 12 volt AC from TR2 to the secondary of TR1 so that a 230 volt potential instantly becomes available at the other end of TR1.

This voltage is fed to the voltage-firing stage consisting of the SCR1 as the main active component along with a few diodes, resistor and the capacitor C4.


The fired voltage from SCR1 is dumped into the primary winding of the ignition coil, where it is instantly pulled to a massive 20,000 volts at its secondary winding. This voltage may be suitably terminated into the fencing.

The high voltage generated by this electric fence charger will need to be carefully applied across the whole length of the fence. 

The two poles from the ignition coil connected to the fence wiring should be kept at least 2 inches apart. 

The pillars of the fence should be ideally made of plastic or similar non conducting material, never use metal and not even wood (wood tend to absorb moisture and may give path to leakages).

Parts List

R4 = 1K, 1WATT,
R5 = 100 OHMS, 1WATT,
P1 = 27K PRESET
C4 = 105/400V PPC,
ALL DIODES ARE 1N4007,
IC = 555
TR1 = 0-12V/3Amp (120 or 230V)
TR2 = 0-12V/1Amp (120 or 230V)
BOTH THE SCRs ARE C106 OR PREFERABLY BT151,

TWO WHEELER IGNITION COIL IS SHOWN IN FLUORESCENT BLUE COLOR


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