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Need help about switch power supply circuit

AdhiWay

Mar 15, 2022
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I'm trying to made a switch mode power supply I found on google (picture below) but as soon I connect the power 150v AC the resistor 12ohm which is connected between transistor emitter and ground burns out immediately, and the transistor start getting hot immediately.
Transistor I'm using is E13007F2 I also tried with C4106 transistor.
I have made the transformer coils: 200 turns of the input coil with very thin wire, 50 turns of auxiliary coil with the same wire, and 40 turns of the output coil with more larger wire.
I appreciate any help.IMG_20230703_133347.jpg2021041414152920.jpg
 
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AnalogKid

Jun 10, 2015
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Please post a link to the source of the circuit.

The transistor symbol has no indication of its polarity - NPN or PNP. Also, which side of the schematic is the input, and which is the output?

ak
 

Alec_t

Jul 7, 2015
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What is the transformer core material?
Are you sure the coil phase relationship is correct, to ensure oscillation?
Are you aware the secondary is not mains-isolated, so there is a shock risk?
 

AdhiWay

Mar 15, 2022
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Please post a link to the source of the circuit.

The transistor symbol has no indication of its polarity - NPN or PNP. Also, which side of the schematic is the input, and which is the output?

ak
Please post a link to the source of the circuit.

The transistor symbol has no indication of its polarity - NPN or PNP. Also, which side of the schematic is the input, and which is the output?

ak
Thank you for helping, I have added the original diagram, I'm using NPN I have mentioned it part number: E13007F2, also I tested it with C4106
 

kellys_eye

Jun 25, 2010
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Are you aware the secondary is not mains-isolated, so there is a shock risk?
There are separate GND/GDD symbols such that, assuming they are adhered to, will give the required safe isolation.

I would suggest, as above, that the phase relationship (feedback) is incorrect.
 

Delta Prime

Jul 29, 2020
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What does this have to do with the topic?!!.
I was curious I've never seen an RMS voltage stated as 150vac.Just curious? I understand based on distribution load demand that value may swing drastically minimum to Max. I meant no offense. It really doesn't matter.
No answers needed.
It could be 10kVac ohm's law
Or any laws that govern is not going to change.
 
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AnalogKid

Jun 10, 2015
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Your location tells us about the power distribution in your area, things such as average voltage, the typical voltage range, power quality and stability, etc. It also can tell us something about the electronic components andmaterials you have access to.

ak
 

AdhiWay

Mar 15, 2022
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I was curious I've never seen an RMS voltage stated as 150vac.Just curious? I understand based on distribution load demand that value may swing drastically minimum to Max. I meant no offense. It really doesn't matter.
No answers needed.
It could be 10kVac ohm's law
Or any laws that govern is not going to change.
in my country it's 220v but recently in my region it's seems has dropped to around 150v, at least this is the reading I'm getting from the multi-meter.
 

kellys_eye

Jun 25, 2010
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in my country it's 220v but recently in my region it's seems has dropped to around 150v, at least this is the reading I'm getting from the multi-meter.
Woah...! Check your meter against a known GOOD supply voltage first then. Mains voltage is quite heavily regulated in many countries and must meet standards for voltage and frequency (many, not ALL countries).

Any assumptions/design must be made on the premise that the input supply is as it is supposed to be - circuitry that requires a stable voltage to operate correctly will not do so if that parameter is incorrect unless the design incorporates automatic compensation for loss/drop of supply voltage.

What make/model is your meter?
 

73's de Edd

Aug 21, 2015
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Sir AdhiWay . . . .
Combine all of the answers you already received and you will have solved the problem.
My only request is your confirming that the transformer core materiel that you used is of the ferrite family . . .as specified *****. . . and that you are NOT trying to use a common silicon steel E-I core . . . . .since the shown resultant
primary inductance and resonating capacitance suggest of a 50-100k operating frequency . . . load dependent / sliding .
.....***** . . . . . .


CHANGES . . .

On your drawn schematic erase the bottom left corner connection of the 12Vsupply ground (COLD) and the right sides AC line N ground (HOT) as the twain shall never meet !
Put an NPN emitter tail on the transistor.
At the left sides rectifiers, put in their . . . .mooooooooore than adequate 470 ufd filter.
Note that they are using an E13003, while you are using the EVEN heftier breakdown of the E13007 or / as well as its twin 2SC4416.
Sooooooooooo . . . . your 12 ohm smoked . . . . maybe opened . . .but did both transistors not short out C-E during that / those power ups . . . . or were you quick to pull the AC plug ? and saved them ?
This is an appropriate time to mention that with FULL raw dc coming thru that 680K is enough hard turn on of the E13007 / or / 2SC4416 to create exactly what has happened to you.
BECAUSE ? . . . of incorrect /opposite polarity feed back at turn on from the 9 turn feedback winding.
Cross / swap its wires and see if that permits start up oscillation and makee workee-workee.

A Timely Technical Tip . . . . .
A . . . . 100 millisecond visual alert . . . . (As that's just about your fastest neuro-bio-mechanical response capability)
Put a LED and series current limiting resistor across that units 12VDC output.
(LED + ~1k resistor that you have already solved the polarity and wiring connections and pre tested on a 12V or 9V battery source.)

Now when you swap feedback polarity, upon then just powering up, if you don't see that test lite immediately . .
PULLA- DE- PLUG !

THAAAAAAAAASSSIT . . . .

73's de Edd . . . . . . .

As a w i i i i i i ld and craaazzzeee teenager, it was only when I bought an INDIAN motorbike, that I found out that adrenaline is brown.

( And flows from BOTH proximal and distal orifices! . . . . . . . frequently . . . . SIMULTANEOUSLY ! )
.
 
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AdhiWay

Mar 15, 2022
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Woah...! Check your meter against a known GOOD supply voltage first then. Mains voltage is quite heavily regulated in many countries and must meet standards for voltage and frequency (many, not ALL countries).

Any assumptions/design must be made on the premise that the input supply is as it is supposed to be - circuitry that requires a stable voltage to operate correctly will not do so if that parameter is incorrect unless the design incorporates automatic compensation for loss/drop of supply voltage.

What make/model is your meter?
the meter I have is a Chinese shitty one, it's model is DM6266, I like making electronics circuit but t do it just as a hobby so I can't buy expensive tool.
 

Delta Prime

Jul 29, 2020
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the meter I have is a Chinese shitty one, it's model is DM6266, I like making electronics circuit but t do it just as a hobby so I can't buy expensive tool
That's okay we just want you to be safe! That's why I asked. Would you happen to notice if you have any machinery household appliances or anything, connected to the mains were you took your measurements with the meter that are not working properly?
 

AdhiWay

Mar 15, 2022
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That's okay we just want you to be safe! That's why I asked. Would you happen to notice if you have any machinery household appliances or anything, connected to the mains were you took your measurements with the meter that are not working properly?
Thank you for your concern, I appreciate that, I will buy another meter not much expensive than the first one, I hope it will better.
Do you have any advice about the problems I have with this SMPS circuit? I tread to makes two another SMPS circuits with no success, I also tested it with different transformers, the problem now is no current in the secondary coil!!.
 

AdhiWay

Mar 15, 2022
38
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That's okay we just want you to be safe! That's why I asked. Would you happen to notice if you have any machinery household appliances or anything, connected to the mains were you took your measurements with the meter that are not working properly?
This is the two SMPS circuits I tried to make.
The circuit of the last picture, I didn't used the optocoupler circuit and the Q1-Q2.

RSC-5.jpg13-08-2014Charger-1.jpg
 

Delta Prime

Jul 29, 2020
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This is the two SMPS circuits I tried to make.
The circuit of the last picture, I didn't used the optocoupler circuit and the Q1-Q2
My response is in the form of making general comments and it's not subject to peer review these are generalities nothing specific.So back off!!:cool:
(Just kidding!)

My friend. You cannot do that! Q1 and Q2 along with the support circuitry R6 ,C3 (tank circuit) are necessary for the high frequency switching provided to the transformer which also provides galvanic isolation(no conduction path for safety reasons) From secondary to primary .The feedback circuit the optical coupler provides feedback to Q1 and Q2 to maintain oscillation .do you see Z1 it says 11 volts if the voltage falls below 11 v nothing will work the LED will not work therefore no coupling no communication between the output and input no 12 volts.
I do wish to help you we all do...you need to take some photographs of how you physically connected this circuit don't be shy. Take photos of your board that you have built we know you do it as a hobby you will not be criticized for this it is the only way I can see we can help you and that's what we are here for. Be safe and take some photos please both sides of the board thank you.
1688572435107.png
 
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