Vpp Programming Supplies Features High Repetition Rate

Programming old EPROM devices needs high voltage, and this is a circuit of high repetition rate Vpp programming supplies. This circuit is used for memory programming that need higher repetition rate. This circuit produces the Vpp continuously by the switching regulator that runs continuously. To preclude any possibility of inadvertent Vpp output, the switching regulator mus t be turned of by driving the Vpp lock line. This is the figure of the circuit;


The LT1072 loop comes on if the Vpp lock goes low, stabilizing at about 17V. This circuit has a clean rise time because of the two pole compensation. The LT1004 reference is biased by the 74C04 when the Vpp command line is low. The A2 and A1 give a scaled output and the LT1004 clamps at 1.23V. To control loop slewing, this circuit uses 680pF that also erase the overshoots. [Circuit diagram source: Linear Technology Application Note]
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Variable Voltage Regulator Circuit Using LM317T

This is a Variable Voltage Regulator Circuit that is built by LM317T IC. The LM317T is an adjustable 3 terminal positive voltage regulator capable of supplying in excess of 1.5 amps over an output range of 1.25 to 37 volts. The device also has built in current limiting and thermal shutdown which makes it essentially blow-out proof. This circuit can be use to make a stable power supply. You can looks the circuit diagram from the figure.


The principle work of the circuit is output voltage is set by two resistors R1 and R2 connected as shown below. The voltage across R1 is a constant 1.25 volts and the adjustment terminal current is less than 100uA. The output voltage can be closely approximated from Vout=1.25 * (1+(R2/R1)) which ignores the adjustment terminal current but will be close if the current through R1 and R2 is many times greater. A minimum load of about 10mA is required, so the value for R1 can be selected to drop 1.25 volts at 10mA or 120 ohms. Something less than 120 ohms can be used to insure the minimum current is greater than 10mA. The example below shows a LM317 used as 13.6 volt regulator. The 988 ohm resistor for R2 can be obtained with a standard 910 and 75 ohm in series.

When power is shut off to the regulator the output voltage should fall faster than the input. In case it doesnt, a diode can be connected across the input/output terminals to protect the regulator from possible reverse voltages. A 1uF tantalum or 25uF electrolytic capacitor across the output improves transient response and a small 0.1uF tantalum capacitor is recommended across the input if the regulator is located an appreciable distance from the power supply filter. The power transformer should be large enough so that the regulator input voltage remains 3 volts above the output at full load, or 16.6 volts for a 13.6 volt output.

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ATX Power Supply PIN OUT Connector

CPU
power supply units (PSU) cede the power to the PC hardware via a
numeral of cables with connectors. The generic specifications in
support of various PSU form factors intended for get through with
desktop systems are defined arrived Intels design guides, which are
periodically revised. The hottest standard is Design conductor rev.1.2
released on February 2008. This detail combines the supplies
representing ATX12V and its five variations.
Main Power Connector ATX Power Supply


For SMPS PSU surgical treatment basics envisage power supply tutorial.
Standard
ATX-type power food for desktop PCs typically gain the key power
connector and other 12V connectors, like well as peripheral, floppy
drive, run ATA, and PCI Express® receptacles.
To
support 75W PCI Express® necessities, arrived the contemporary ATX
systems the old 20-pin major connector has been replaced by a 24-pin
connector. Accordingly, distinct ATX-shape smps possibly will
application different total of power supply wires: see the diagram in
favor of pinouts of the old and new power connectors. The flag in this
chart characterize recommended ensign of the wires wearing the PSU
cables. The flag are publicized at this time absolutely for reference
(you wont investigate them from the front). The diagrams contemplate
the front (pin-border) see. You need to look from the back of the
connector to see the decorated wires. key connector uses Molex Housing
Mini-Fit Jr. P/N# 39-01-2240 or else equivalent (old part quantity
5557-24R), contacts: Molex 44476-1112 or else equivalent, mating
motherboard connector is Molex 44206-0007. The old 20-pin ATX connector
was Molex 39-01-2200 otherwise equivalent, mating motherboard part was
Molex 39-29-9202. Under some conditions new-fangled PSU can still ensue
used in the field of an old PC and vise versa- distinguish our
handbook on linking 20-pin PSU to 24-pin motherboard. 

To
start up a halt by yourself PSU on behalf of hard purposes, you need
to curt PS_ON pin to lone of the unexceptional pins. Under natural
surgery, PS_ON is activated as soon as you press and statement the
mainframe power button while it is fashionable maintain mode. 

All
voltages are referenced to the same common (if you need to assess in
the least voltage, associate the return be the forerunner of your
voltmeter to any of the COM pins).

Memorandum
to Apples Power Macs, basin (flanked by 1996 and 2000) and particular
HP models habit proprietary (non-standard) motherboards with entirely
changed pinouts.

The
rated current of the core Molex connector is 6A for every pin. Which
revenue with the old 20-pin comfort you cant grasp added than 18A from
3.3V and 24A from 5V. with the intention ofs why inwards premature
2000s, particular motherboards with 3.3V >18A and 5V >24A
(principally dual CPU AMD systems) used an assisting 6-pin power cable.
It was disinterested from ATX12V spec v2.0 in 2003 as especially pins
were added to the highest connector. in place of added in sequence on
form factors set eyes on our workstation PSU leader and schematics. 

SATA Power COnnector circuit

While
the industry began using voltage law modules (VRM) running rancid 12V2
to energize CPU and other motherboard components, the bulk of the
wattage shifted to 12 volt means of transportation. as a rule of at
presents motherboards supply their CPU with a separate 12 volt cable,
which has 4 pins pro ATX smartness (from time to time called P4) before 8
or additional pins for EPS and non-standard climax-power systems. a
quantity of PSUs may possibly gain three before four 12 volt 4-pin
connectors. The part total for standard 4-pin connector is Molex
39-01-2040 before equivalent.

4-pin
peripheral power connector progress to CD drives, fans, and other
lesser campaign. The floppy drive connector such as the forename implies
powers the floppy drive. 

Record
to facilitate pin information and wire numbers clothed in run Power
ATA (SATA) connector are not 1:1. at hand are three pins in support of
all voltage. solitary pin from each voltage is used for pre-charge in
the backplane. Mating ongoing plug of ATA campaign contains both
signify and power segments.

About
units could in addition arrange an elective 2x3 connector to
facilitate can be situated used on behalf of additional functions, such
since fan monitoring and control, IEEE-1394 power source, and a remote
sensation of 3.3 vs.. 

PSU
larger than 450W designed for extreme-bottom discrete graphics cards
normally have further 2x3 before 2x4 connectors. They supply especially
power to graphics to require extra than 75 watts whole. 
The 6-pin PCI Express® power connector is Molex part digit 0455590002.

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DIy a wireless fm transmitter test



The photo shows a wireless FM transmitter, pocket radio and yellow disk
for size comparisons. Speak into the transmitter and others hear you
on any FM radio. The transmitter can be built in an afternoon with
simple, affordable and widely available parts. Construction is fun and
much can be learned although performance is modest; for example, your
voice gets difficult to hear at distances greater than 25 feet.


Motivation and Audience

Our
long-term goals with such circuits are in remote control and data
acquisition. Touch tones could be transmitted to wirelessly turn on/off
a robots actuators. Sensor data could be converted into morse-code
like sounds and deciphered by a microcontroller to wirelessly monitor
environments. This tutorials audience would be also motivated by such
applications. Building a simple FM transmitter would be a first-step
towards such goals.
Not to give you false expectations, this FM
transmitter is far from perfect offering only modest performance.
First, tuning the transmitter can be frustrating. Even slight turns in
the variable capacitor can result in large frequency changes. Second,
transmitter tuning often resulted in a harmonic frequency. Instead of
the intended 108 MHz for example, capacitor tuning yielded a 216 MHz
transmitter frequency. In addition to hearing your voice one could
slightly hear radio station broadcasts.

If performance is modest, why would I build this transmitter?
One
answer is that much can be learned and this tutorial is is appendixed
with the underlying mathematics to calculate parameters like (1)
tranmitter frequency, power output and range (2) antenna length and (3)
required coil winding. Often on the web, one just finds a schematic.
By adding the analysis (with high school level math), one can conceive
improvements on transmitter performance.
This tutorials audience is thus electronics enthusiasts who:
    • dont have much FM or radio-frequency (RF) experience
    • want to build an FM transmitter
    • want to learn how such transmitters work
    • want to learn how components are selected e.g. calculating the number of turns when building an air coil, antenna length etc.


Again
this tutorial emphasizes that the transmitters performance is modest,
but is learned in its construction. The tutorial breakdown is as
follows:

  • Parts List and Sources
  • Construction/Schematic
  • Theory
  • Operation
  • Where To Go From Here
  • Author Information

Parts List and Sources

US-based
vendors include Jameco, Digikey, JDR and Radio Shack. Note: Boondog
has no association with these vendors. Attempts were acquire all parts
from a single vendor. Part numbers for common resistors are not given.

TABLE 1: FM TRANSMITTER PARTS
PART DESCRIPTION VENDOR PART PRICE (1999) QTY
2N2222 (TO-18 CAN CASE) NPN TRANSMITTER JAMECO 38236 0.39 1  
ELETRET MIC 4.5V LOW IMPEDENCE JAMECO 136573 0.75 1  
4 TO 30 PF VARIABLE CAPACITOR JAMECO 32838 0.99 1  
SPST SWITCH JAMECO 76523 1.09 1  
BR2325 3V COIN CELL JAMECO 11789 1.95 2  
BATTERY HOLDER FOR TWO CR2325 CELLS JAMECO 38543 0.66 1  
10 KOHM RESISTOR       2  
4.7 KOHM RESISTOR       1  
47 OHM RESISTOR       1  
10 UF ELECTROLYTIC CAP JAMECO 158529 0.09 1  
0.01 UF CERAMIC CAP JAMECO 15229 0.05 1  
PROTOTYPING BOARD 1.6X2.7 SQ.IN JAMECO 105099 4.95 1  
4.7 PF CERAMIC CAP RADIO SHACK 272-120 0.49 1  
(OPTIONAL) 34.75 INCH TELESCOPIC ANTENNA RADIO SHACK 270-1402 3.99 1  
(OPTIONAL) MAGNET WIRE 22 GAUGE RADIO SHACK 278-1345 3.99 1  
SODA STRAW McDONALDS   FREE 1  
 
An
effort was made to find a single source supplier of all parts. Jameco
has almost every part cited in the tables. Details construction your
air core inductor using a McDonalds soda straw will be described in the
next section.

Construction

A combination of
wirewrapping and soldering was used to construct the FM transmitter.
Jamecos prototyping card provides enough room for (non-critical) part
placement. You should try to keep all parts close together and keep
wire leads short. The photos below illustrate possible part placement
(left) and the solder side (right).


Schematic

fmTx031402a.pdf is the Acrobat file of the same schematic. You will need Adobes free Acrobat reader to view it.

The schematic and constructing the circuit are relatively
straight-forward. Some highlights and clarifications towards circuit
construction are given next.

Electret Microphone

An
electret microphone has two pins which connect to the positive and
negative leads of a battery. As shown in the drawing below, one looks
at the bottom of the electret microphone. The pad that physically
touches the microphones casing connects to the batterys negative lead.


Batteries

You
can replace the coin cells, typically found in calculators and
watches, with regular 1.5V AA, C or D-cells. The coin cells however
take less room and can solder onto the protoboard.

2N2222A Transistor

The
2N2222A is a very common NPN transistor. The one used here (Jameco
#38236) is the metal can type (TO-18 casing). Its three pins are for
the transistors base (B), collector (C) and emitter (E). There is no
standard pinout for transistors. As such, request the transistors spec
sheet when ordering it to identify the pinout, or if you own a
multimeter with a transistor tester, use it.
The 2N2222A also
comes in a black plastic casing (TO-92 style) which you can use if you
want. The T0-18 is preferred because the can has a small tab that typically represents the emitter pin.

Make sure you correctly identify the 2N2222As pinout and correctly
wire the base, collector and emitter in the schematic. Often, circuit
malfunctions because the pins were mis-wired.

Variable Capacitor

The
leads for the variable capacitor do not fit in normal 0.1 inch
protoboards. You can dremel-drill into the protoboard to make the leads
fit. Alternatively you can solder wire to the leads, but if you do,
keep wires as short as possible in order to avoid stray capacitances.

Inductor

An
inductor is just a coil of wire and you need to wind one for this
circuit. An inductor is characterized by its length, radius and the
number of turns of wire in the coil. Magnet wire (Radio Shack part
278-1345) was used to build the inductor but you can use standard solid
strand 22 AWG gauge copper wire.
Some on-line and printed
articles describe winding the wire around a pencil. Unfortunately,
pencils come in different diameters and hence a McDonalds soda straw
was used; the yellow-red-white striped straw, found in every McDonalds
in the world, is the same size. The straws radius is exactly 0.1325
inches (diameter = 0.2650 inches) and 1/4 inches was snipped off the
straw.

Next,
a straight piece wire was wound around this 1/4 inch snippet six times
and then soldered on the prototyping board. The end result is an
inductor (also known as an air core coil) with an
0.1325 inch radius. If you wish, you can apply some womens clear
fingernail polish to permanently keep the wire on the straw snippet.


Antenna

A
30 inch long piece of 22 gauge solid stramd copper wire is a suitable
antenna. However when carrying the transmitter, you risk tangling the
wire. As such you can screw a telescopic antenna, like ones found a
radios, into the prototyping board.

Theory: How does the FM Transmitter Work?

The
variable capacitor and your self-made inductor will vibrate at
frequencies in the FM radio band (88 to 108 MHz). The electret
microphone has a resistance that depends on how loudly you speak into
it. This microphone is battery powered and according to the V=IR
Ohms Law, changes in resistance for fixed voltage will result in
proportional changes in current. This current feeds into the base of the
2N2222 NPN transistor which is connected to your variable capacitor,
inductor and antenna. The net effect is that depending on your variable
capacitors value, your voice will be modulated to transmit at a
frequency between 88 and 108 MHz. If a nearby pocket FM radio is tuned
to this frequency, youll be heard when speaking into your transmitter.

The component values in the circuit are derived to better
understand how this FM transmitter will work. The underlying math is
rather simple and can be found in most undergraduate university physics
textbooks.

Inductance of an Air Core Coil

Your self-made inductor has a value determined by its radius r, length x and number of wire turns n.

For your McDonalds soda straw inductor, r = 0.1325 inches, x = 0.25 inches and n = 6 turns and results in L = 0.171 microHenry or 0.000000171 Henry.
The specific frequency f generated is now determined by the capacitance C and inductance L measured in Farads and Henry respectively:


Resonant Frequency of a Parallel LC Circuit

FM
radio stations operate on frequencies between 88 and 108 MHz. The
variable capacitor and your self-made inductor constitute a parallel LC
circuit. It is also called a tank circuit and will vibrate at a resonant frequency which will be picked up your pocket FM radio.

In tank circuits, the underlying physics is that a capacitor
stores electrical energy in the electric field between its plates and an
inductor stores energy in the magnetic field induced by the coil
winding. The mechanical equivalent is the energy balance in a flywheel;
angular momentum (kinetic energy) is balanced by the spring (potential
energy). Another example is a pendulum where theres a kinetic versus
potential energy balance that dictates the period (or frequency) of
oscillations.
Given your variable capacitor ranges from 4 to 34
pF, your tank circuit will resonant between 66 and 192 MHz, well within
the FM radio range. To compute these values for different values of C, n, r and x
a simple Excel spreadsheet, called calcFreq.xls was created. Simply
enter the values and the inductance and frequency are automatically
calculated.

Antenna Length

You built your
antenna either with a piece of solid strand 22 gauge wire 30 inches
long or used a telescopically extendable antenna. Its length should be
approximately 1/4 the FM wavelength; recall that multiplying frequency
and wavelength equals the speed of light. Youll most probably be
operating your transmitter near 108 MHz, as such:


Fixed Capacitors

Referring to the schematic, C2 and C4 act as decoupling capacitors and typically 0.01 uF (or 0.1 uF) are used. C4 attempts to maintain a constant voltage across the entire circuit despite voltage fluctuations as the battery dies.

A capacitor can be thought of as a frequency-dependent resistor
(called reactance). Speech consists of different frequencies and the
capacitor C1 impedes them. The net effect is that C1 modulates the current going into the transistor. Using a large value for C1 reinforces bass (low frequencies) while smaller values boost treble (high frequencies).
The C3
capacitor across the 2N2222A transistor serves to keep the tank
circuit vibrating. In theory, as long as there is a supply voltage
across the parallel inductor and variable capacitor, it should vibrate
at the resonant frequency indefinetely. In reality however, the
frequency decays due to heating losses. C3 is used to prevent decay and the 2N2222A spec sheet suggests a capacitance between 4 to 10 pF.

Resistor for Electret Mic

The spec sheet for the Jameco #136573 electret microphone says the maximum current is 0.5 mA. When battery powered at 6V, then the voltage drop across R1 is V1 = 1.92V. The resulting current through the microphone is below the rated maximum since

I1 = (6-1.92)V / 10000 Ohms = 0.41 mA

Resistors and the 2N2222A

The 2N2222A transistor has rated maximums thus demanding a voltage divider made with R2 and R3 and emitter current limiting with R4.
The 2N2222As maximum rated power is Pmax = 0.5 W.
This power ultimately affects the distance you can transmit.
Overpowering the transistor will heat and destroy it. To avoid this,
one can calculate that the FM transmitter outputs approximately 124 mW and is well below the rated maximum. The mathematical details are given in rfMath.pdf.
The power is intimately related to the transmission range. At 124 mW
and 30% radiation efficiencies, the maximum distance between your FM
transmitter and a battery-powered radio will range betweem 35 to 112
feet. The calculations are given in rfDistance.pdf.

Operation

First, use a battery-powered pocket radio as a receiver. AC powered boom-boxes and home stereos (110 or 220 V) are not recommended; battery-powered radios are much better at receiving transmissions than AC-powered units.

  1. Tune your radio to dead air, i.e. frequencies within the FM radio band that are silent or only have some hiss. Frequencies near 108 MHz
    are typically dead air. The Radio-Locator web page lists local radio
    stations in your area. This can help you identify dead air frequencies.
  2. Turn
    on your FM transmitter, extend its antenna and keep the transmitter
    approximately 2 feet away from your FM radio. Speak into the mic while slowly
    adjusting the variable cap. Use your fingernail or non-metallic
    screwdriver until you hear yourself over the radio. This process is
    frustratingly tedious, requiring careful capacitor tuning. You are tuned
    once you hear howling (also known as a hot mic) which indicates transmitter-receiver feedback.
  3. Increase the transmitter-to-radio distance. Congratulations - you have a wireless microphone!

Where To Go From Here

As
stated earlier, performance is modest. The authors experience
operating in a major city (Philadelphia, USA) with the battery-powered
radio tuned at 108 MHz yielded approximately 25 feet indoors and 50 feet
outdoors. Also, in addition to the authors voice, radio station
broadcasts could be slightly heard.
To tweak performance, a
spectrum analyzer can be used. Its a device that visually displays
frequencies are most predominant. The author discovered the circuit was
transmitting at approximately 200 to 220 MHz, rather than the desired
108 MHz! 216 MHz is a harmonic, being twice the desired 108 MHz.
Transmission range is thus reduced and susceptible to noice (radio
station broadcasts).
To transmit at the desired 108 MHz, the author considered the following:

  • A hand-made coil thats 0.1 uH is difficult to test. Inductance meters to measure at the micro Henry range are expensive.
  • Capacitance meters measuring picoFarads are also expensive.
  • A 0.111 uH air core coil was purchased from Coilcraft, an inductor manufacturer.
  • Spectrum
    analyzers costs thousands of dollars. A viable alternative is an $130
    USD Elenco F-2800 frequency counter. This is a nice unit to acquire if
    you plan on building FM transmitters more seriously.
For the
most part, the frequency counter displayed approximated 200 MHz even
with the Coilcraft inductor! Thus most probably the variable capacitor
is not truly giving a 4-to-34 pF range. Since the transmission
frequency stayed closed to 200 MHz, calcFreq.xls reveal that variable
capacitor actually stays close 4 pF rather than going up to the rated
34 pF. This should be expected since tolerances in capacitance are
rarely precise. The net effect is that without picoFarad resolution
capacitance youll be transmitting at a 216 MHz harmonic yielding
reduced range and susceptible to noise.

Final Words

This
tutorial along with appendixes detail fully a single transistor FM
transmitter construction and underlying math. The circuit can be built
in an afternoon with less than $10 USD of common parts, resulting in a
25 to 50 foot transmission range.
Like the author, readers might
be excited about the prospects of building FM transmitters. Many
circuit designs and schematics exist on-line and in print but dont
often provide much analysis. This tutorial attempts to fill this gap,
especially for first-time FM transmitter builders. The analysis allows
one to learn what roles and their values play in the circuit. Such
analysis provides a reader a stepping point towards improving or
customizing the circuit.
Illustrating the math and real-world
operation is the tutorials value. Some material towards learning more
might be acquired from the references below. Happy building!
Read Full article[...]

Electrical Goods Equipment Supplies Precision Electricals House Wiring

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Electrical Wiring In The Home Outlet As Power Source Philadelphia.


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Have Separate Wiring To Carry Energy Loads To And From The House.


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Electrical Floorplans With Power Low Voltage And Structured Wiring.


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250 And 525 Sx Mxc Exc Electrical System And Wiring Diagram Here.


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How To Connect Home Electrical Wiring From A House Panel To A Garage.


House Electrical Wiring on House Wiring
House Wiring.


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Electrical Goods Equipment Supplies Precision Electricals House Wiring.


House Electrical Wiring on Or Residential Home With Basic Electrical Wiring And Hvac Complete
Or Residential Home With Basic Electrical Wiring And Hvac Complete.


House Electrical Wiring on House Electric Wiring Diagram Home Branch Circuits Home Electrical
House Electric Wiring Diagram Home Branch Circuits Home Electrical.


House Electrical Wiring on Way Switch Wiring Diagram Variation  3   Electrical Online
Way Switch Wiring Diagram Variation 3 Electrical Online.


Read Full article[...]

Simple Transformerless 5 Volt Power Supply

Description

An increasing number of appliances draw a very small current from the power supply. If you need to design a mains powered device, you could generally choose between a linear and a switch-mode power supply. However, what if the appliance’s total power consumption is very small? Transformer-based power supplies are bulky, while the switchers are generally made to provide greater current output, with a significant increase in complexity, problems involving PCB layout and, inherently, reduced reliability. 

Is it possible to create a simple, minimum part-count mains (230 VAC primary) power supply, without transformers or coils, capable of delivering about 100 mA at, say, 5 V A general approach could be to employ a highly inefficient stabilizer that would rectify AC and, utilizing a zener diode to provide a 5.1 V output, dissipate all the excess from 5.1 V to (230×v2) volts in a resistor. Even if the load would require only about 10 mA, the loss would be approximately 3 watts, so a significant heat dissipation would occur even for such a small power consumption. 

At 100 mA, the useless dissipation would go over 30 W, making this scheme completely unacceptable. Power conversion efficiency is not a major consideration here; instead, the basic problem is how to reduce heavy dissipation and protect the components from burning out. The circuit shown here is one of the simplest ways to achieve the above goals in practice. A JVR varistor is used for overvoltage/surge protection. Voltage divider R1-R2 follows the rectified 230 V and, when it is high enough, T1 turns on and T3 cannot conduct.

Circuit diagram:



When the rectified voltage drops, T1 turns off and T3 starts to conduct current into the reservoir capacitor C1. The interception point (the moment when T1 turns off) is set by P1 (usually set to about 3k3), which controls the total output current capacity of the power supply: reducing P1 makes T1 react later, stopping T3 later, so more current is supplied, but with increased heat dissipation. Components T2, R3 and C2 form a typical ‘soft start’ circuit to reduce current spikes this is necessary in order to limit C1’s charging current when the power supply is initially turned on. At a given setting of P1, the output current through R5 is constant. 

Thus, load R4 takes as much current as it requires, while the rest goes through a zener diode, D5. Knowing the maximum current drawn by the load allows adjusting P1 to such a value as to provide a total current through R5 just 5 to 6 mA over the maximum required by the load. In this way, unnecessary dissipation is much reduced, with zener stabilization function preserved. Zener diode D5 also protects C1 from over voltages, thus enabling te use of low-cost 16 V electrolytics. 

The current flow through R5 and D5, even when the load is disconnected, prevents T3’s gate-source voltage from rising too much and causing damage to device. In addition, T1 need not be a high-voltage transistor, but its current gain should exceed 120 (e.g. BC546B, or even BC547C can be used).

CAUTION!

The circuit is not galvanically isolated from the mains. Touching any part of the circuit (or any circuitry it supplies power to) while in operation, is dangerous and can result in an electric shock! This circuit should not be built or used by individuals without proper knowledge of mains voltage procedures.




Copyright: Elektor Electronics Magazine
Author: Srdjan Jankovic & Branko Milovanovic
Read Full article[...]

Fuse Box Toyota 1998 2000 Sienna Diagram

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Fuse Box Toyota 1998-2000 Sienna Diagram



Fuse Box Toyota 1998-2000 Sienna Diagram
Fuse Box Toyota 1998-2000 Sienna Diagram

Fuse Panel Layout Diagram Parts: headlight control relay, head lamp, engine room, head fuse, dome fuse, ECU fuse, headlight dimmer relay,daytime running light resister, headlight, daytime running lamp fuse.
Read Full article[...]

2004 Chevrolet Avalanche Wiring Diagram

2004 Chevrolet Avalanche Wiring Diagram
(click for full size image)


The Part of 2004 Chevrolet Avalanche Wiring Diagram: power distribution, fuse block, battery, antenna, relay block, data link connector, audio signal, blunt cut, bare, drain wire,

Read Full article[...]

Ford E250 Engine Compartment Fuse Box DIagram

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Ford E250 Engine Compartment Fuse Box DIagram



Ford E250 Engine Compartment Fuse Box DIagram
Ford E250 Engine Compartment Fuse Box DIagram

Fuse Panel Layout Diagram Parts: A/C heater, remote keyless entry module, powertrain control module, PCM power relay, electroni brake, power seats, power lumbar seats, blower motor relay, ignition switch, fuel pump relay, trailer battery charge relay, trailer adapter battery, trailer back up lamp relay, traile running lamp relay, plug in diode, stop lamp, trailer running lamp, DRL module, horn relay, main light switch, auxiliary battery, ignition system, instrument cluster, 4WABS relay.
Read Full article[...]

Contactless AC Mains Voltage Detector

This is a CMOS IC (CD4033) based circuit which can be used to detect presence of AC mains voltage without any electrical contact with the conductor carrying AC current/voltage. Thus it can be used to detect mains AC voltage without removing the insulation from the conductor. Just take it in the vicinity of the conductor and it would detect presence of AC voltage. If AC voltage is not present, the display would randomly show any digit (0 through 9) permanently. If mains supply is available in the conductor, the electric field would be induced into the sensing probe. Since IC used is CMOS type, its input impedance is extremely high and thus the induced voltage is sufficient to clock the counter IC. Thus display count advances rapidly from 0 to 9 and then repeats itself. This is the indication for presence of mains supply. Display stops advancing when the unit is taken away from the mains carrying conductor. For compactness, a 9-volt PP3 battery may be used for supply to the gadget.

Contactless AC Mains Voltage Detector circuit diagram
Read Full article[...]