How to make a 12v 5Amp transformerless or electronic power supply which is Switched Mode Power Supply (SMPS) based

How to make a 12v 5Amp transformerless or electronic power supply which is Switched Mode Power Supply(SMPS) based.

By: Alok kumar

Making a 12v 5A Transormerless electronic power supply is really a complicated task and if we made it the resulting circuit will become a bulky circuit. Don't worry about it, Now we are going to solve it together.

In this post, We are going to take advantage of High frequency method over a small transformer or inducuctors coupled together over a ferrite core, This method also known as Flyback Converter type design. As we all know at High frequency, we can make a small transformer conduct even much higher current or power far above the rated...
specification without damaging it. So just use this property to exploit the small transformer to get high amperage from a little ferrite transformer. Simply switch mode power supply simply the property of inductor that it always opposes the rate of change of current flowing through. So simply by switching on and off the inductor will result in boosted output across the inductor with opposit polarity. The simplest switch mode power supply (smps) are boost converter circuit but it is not a isolated power supply from mains so today we are going to make a flyback converter power supply (smps based) to get a highly regulated output by using a beedback by optocoupler to tightly regulate output and is also isolated from the mains supply also for our 12 volt 5 ampere electronic supply which is switch mode power supply ( smps based) to be stable tightly regulated and isolated like we need .

How to Regulate Power Supply Voltage in Electronic circuits Or Reduce voltage dropping

How to Regulate Voltage in  Electronic Circuits or Reduce voltage dropping in power supplies.

By: Alok kumar

Generally the sole purpose of a power supply is to provide power to an electronic circuit so that we can operate that circuit within safe voltage and current tolerance/ range. For a given amount of power, there is an inverse relationship between voltage and current (ohm's law V=IR, where v is voltage across the circuit, I is current in the circuit and R is the equivalent resistance across the circuit). Whenever there is an increase in current there must be a voltage, and whenever current decreases,voltage must increase. This simple phenomenon unfortunately, has an adverse effect on power supply circuits.

When anyone connect a voltmeter to the output terminals of a power supply, the voltmeter itself draws current ( but an almost of insignificant amount ) so the meter reads very close to the voltage anyone should expect to obtain from the power supply.

However, if one connect a circuit which draws a significant amount of current from the power supply, then there will be a voltage drop occurs in perportion to the amount of current.


Depending on the nature of the circuit one is connecting to the power supply, this voltage drop
may or may not be a bad thing for most of circuit which is insensitive to voltage variation but some circuits which is designed for 12 VDC or some fixed value DC then the circuit may not function properly. In that case the power supply needs to workeven harder to make sure it delivers the desired
voltage to the circuit to function properly.

So power supply have to maintain that value and to maintain that steady voltage level regardless of the amount of current drawn from a power supply, the power supply need to incorporate a voltage regulator circuit. The voltage regulator circuitory usulaay monitors the current drawn by the load and according to that it increases or decreases the voltage accordingly to keep the voltage level fixed or constant.

So simply when a power supply  incorporates a voltage regulator circuitory  is called a regulated power supply.

Anyone can design their own voltage regulator circuit, but it is very easy to buy one of the many
available integrated circuit (IC) voltage regulators in the market to save the time. Generally voltage
regulator ICs are inexpensive and, with we only have to simply connect three pins, really very easy to incorporate into any circuit which requires a regulated power supply. In the market the most popular type of voltage regulator IC is the 78XX series, sometimes it is called as the LM78XX series too. These voltage regulators IC's is the combination of 17 transistors, three
Zener diodes, and a handful of resistors into one easy to use handy package with three pins. We also have to buy a heat sink (aluminium bar) which helps the IC to dissipate the excess power consumed by the regulator for compensation for the increases or decreases in current draw to keep the voltage at a constant level or fixed level.

Simple Light Dark Detector circuit using LDR

How to make very Simple Electronic Dark or Light detector circuit using LDR and Integrating a Relay in it for making it a  Automatic Switch.

By: Alok kumar

Today we are going to learn how to make an eletronic dark or light detector circuit because this marvelous piece of gadget can be very useful if integrated with other devices as a switch. It means when a certain predefined intensity of light is reached our device is able to detect that condition and able to switch any device and can be very useful for saving energy and efforts. We can make a Automatic Lawn Light, Automatic Bulb or Tubelight, Automatic Car Head Light switch and many many useful circuit. It can be used in various ways if logically applied.

How to make Transformerless or Electronic Power Supply/Driver

How to Make Transformerless 12Volt 1 Ampere or 2 ampere or more amperage compact DC electronic Power Supply or Driver/Charger.

By:Alok kumar


Today we are going to learn how to design and make the Cheapest and Smallest Transformerless electronic Power Supply or capacitive power supply 12v 1a or 2a according to our requirement. Actually there are many Power supplies available in the market but most of them are transformer/smps based and are very Big, Bulky, ugly, costly and have very complex circuitary to understand by a complete newbie.


So, lets get started to learn the design procedure so that we will be able to make the desired electronic power supply onward.


The biggest advantage of this explained circuit is that it is independent of input voltages fluctuations to a great extent


Here, we assume the input power source used here is 220V AC OR 110V AC 50~60Hz from home wall socket directly.


COMPONENTS REQUIRED:

C1= 400V, 1395K Capacitor or (Connect three 400v, 475k caramic capacitor in parallel or three 2uf/400v caramic capacitor) (Note if the mains current is 220v AC 50-60Hz if mains is 110v AC then use 250v/1395k).


[The above circuit is Verified and Tested circuit by me and works great, so make it, save money & enjoy.]

WORKING OF ABOVE CIRCUIT

In above circuit, R1 is actually doing nothing, but serve's the purpose of Bleeder Resistance, means it discharges the Charge stored in C1 gradually when the circuit is not in use( it may takes time between 1 to 15 sec according to its value and amount of charge stored).

This power supply is best suited for Capacitive loads like charging the battery, LED Drivers or any capacitive load...

So, By by reading the below post you guys will be able to design and make the power supply of any current rating and voltage rating according to your requirement. So please be focused and attentive to understand the technical specifications.


[Instruction: Above project deals with mains AC current & not isolated from AC mains, So be careful and work always under the guidance of any elder if you are a complete newbie. Please always remember to keep your one hand in pocket whenever working with any live circuit so that in case the current wont pass through your heart just for safety].

USE MALE AND FEMALE JACKS TO AVOID SHOCK BY CHARGED CAPACITOR.

In my next post i m going to post a circuit of 12V 5 ampere transformer less electronic switch mode power supply(or SMPS based) or Driver.


Posts Recommended:

1. Make 30volt 1amp transformerless power supply circuit
2. Make a 12v 5Amp SMPS transformerless electronic power supply
3. Make a 12V 10Amp, 20Amp, 30Amp, 40Amp variable transformerless electronic SMPS power supply
4. Simple 12 v 1 amp SMPS power supply, battery charger, LED driver circuit
5. Make 5V 2A Power supply by IC 78S05 simple circuit
6. Make 5V 1Amp Cell Phone battery Charger Circuit from 220/110v
7. Make 48V Transformerless Electronic Automatic Battery Pack Charger Circuit
8. Make a Laptop charger (efficient and reliable) from a car battery 12v

Today we are going learn a new type of circuit generally known RC circuit or capacitive power supply, which is the simplest and Cheapest circuit you will find ever.


I have created this Circuit during my research on how to increasing the power output of electronic or transformer less power supply for capacitive loads.


So now the question arises here is that - How to make this great and easy piece of Transformerless Electronic Power Supply or LED driver circuit at home.












C1= 400V, 1395K Capacitor or (Connect three 400v/475k or two 2uF/400V capacitor in parallel for 1.2Ampere or higher capacitance for higher current according to the calculations explained below).


R1= 10M ohm or 1M ohm 1watt resistor.


D1-D4= IN5408 (4 DIODES)( just choose diodes which have double ratig for our curent requirement for e.g. for 2 amp choose diode of rating 4 amp...)



R2= 10 ohm 1 or 2 watt.( 2 watt will be better for heat handling or dissipation)



C2= 1000uF(micro faraday) ,50 v ( 2 in number if you finds the output is fluctuating, connect them in parallel for better filtering of ripples produced due to rectification of AC mains current).


z1= zener of 15v to prevent any voltage fluctuations caused due to input voltage fluctuation to regulate our DC output to maximum of 15 volt max in extreme case.


{note: you must add a 10M or 1M ohm as a bleeder resistance parallel to C2 for Discharging the charge stored in C2 otherwise you may get a high current shock or surge current dur to charge stored in the capacitor if this charge is not discharged when circuit is not in operation it is going to remain for very long time and someone may get the shock. In later posts we will learn the techenique to remove any surge current by incorporating a crowbar circuit at the output. So simply to understand better this circuit and make it simple simply connect a higher value capacitor across capacitor C1.}


{Do not touch any terminals with bare hands even the Driver is Unplugged. First discharge the C1 and C2 by shorting the input and output terminal together. there will be spark generated while doing this this means charge stored is discharged completely by you now. Only after that you should touch any terminal, or leave for some time before touching the terminals so that bleeder resistance work for you to discharge the charge stored in capacitor C1.}

Calculations:

If we use 2uF/400V(because it is readily available in the market) THEN :


the capacitive reactance offered by capacitor(2uF/400V) connected at mains supply is:
x= 1/(2*pi*f*c) where pi is 22/7, and f is the frequency of mains supply eg 50Hz or 60Hz
then
now reactance or impidence ( or simply resistance) of whole ckt is = sqrt(R+x) where R is the resistance or load and wires all together attached in circuit and sqrt means squareroot of (R+X)
now out put current i=(v/z) where v= mains voltage 220v or 111v
So you can now calculate the capacitance of circuit according to the required current.


If you want to increase the output current just simply increases the capacitance value of C1 or just by Adding more C1 together in parallel if you are unable to find the appropriate value capacitor in market.


The C2 here only used as a filter to reduce the ripples in the output waveform.( it acts as filter to smoothen the output DC desired.)


Z1 is zener to protect the appliances from overvoltages.


If you want to decrease the voltage rating just use appropriate zener diode

If you wanted to increase the voltage rating of the circuit to double just use doubler circuit to double the voltage but the catch is that the current will become half and frequency become twice means 120Hz. so according to your requirement just increase the output DC current by simply adding high capacitance capacitor or add more C1 in parallel if you need high output DC voltage


For capacitance C1 related calculation problems or any problem regarding this explained circuit please reply in comment section and i will be happy to help by reply ASAP.


If you find above circuit interesting or useful please share it will be our reward from your side.

 Thank you for Reading.