{782} 12 Volt SMPS Has Only 3 Volt Output, Low Output
ฝัง
- เผยแพร่เมื่อ 1 มิ.ย. 2024
- 12 Volt SMPS Power Supply Has Only 3 Volt Output. in this video number {782} i demonstrated and explained how to repair TL494 / KA7500 based half bridge 12 volt 20 ampere smps rafeed model RF-0076, it was providing low output voltage than the rated 12 volt, and there was no control by voltage adjustment potentiometer. i found the pwm controller ic tl494, it was damaged. i replaced the smps controller ic with new one and the power supply started functioning normally
You are Invited to Join Haseeb Electronics
/ @haseebelectronics
how to fixed switch mode power supply SMPS step by step when OutPut Voltage Low
How To Repair Switch Mode Power Supply when the output voltage are less than the rated voltage and it is giving unregulated voltage
How To Repair Switch Mode Power Supply SMPS, When it have low OutPut Voltage
how to repair tl494 half bridge topology power supply circuit,
practical repair of 12 volt 20 amp switch mode power supply SMPS.
after watching this video you can capable to:-
how to repair smps
if SMPS have low output or output voltage unregulated
how to repair computer power supply
how to repair laptop charger
#smps #low #output
i shared very easy & step by step practical troubleshooting / circuit tracing and fault finding techniques to find the faults in any switching mode power supply.
how to repair smps (switch /switching mode power supply), either it is industrial power supply, laptop charger, adapter, computer atx power supply, server power supply, mobile charger, battery charger, inverter welding machine, led / lcd tv power supply, power supply of dth / digital satellite receiver,
how to repair smps (switch / switching mode power supplies) in very easy step by step repair and practical troubleshooting & circuit tracing tutorial
12 Volt Power Supply Have Only 3 Volt Output, how to repair smps, switch mode power supply, very easy repair of SMPS, haseeb electronics, smps output fluctuating, SMPS OutPut Voltage Low, smps repair, smps low output voltage problem, smps repair step by step, switching power supply repair, 12 volt power supply, 12 volt 20 amp power supply, 12 volt 20 amp smps, tl494 smps, tl494 smps circuit, tl494 smps power supply, pwm tl494 smps, smps have 3 volt
00:00 12 volt smps power supply is giving low output voltage
00:30 how to apply power to a circuit for testing (DUT / UUT)
00:49 how to troubleshoot / repair smps power supply
04:47 damaged / cracked TL494 ic
05:07 how to check TL494 power supply circuit - วิทยาศาสตร์และเทคโนโลยี
![เกิดใหม่ทั้งทีก็เป็นสไลม์ไปซะแล้ว ซีซั่น 3 - ตอนที่ 57 [ซับไทย]](http://i.ytimg.com/vi/pNhft3YZFRE/mqdefault.jpg)
good repair 👍👏👋
best regards dear friend
Just one small observation about your logic regarding the soldering of random legs of the IC. Your logic and technical aspect is fine but all these mass produced cards are usually, Wave Soldered in the factory, which means all the legs of the IC are soldered at one go. From what I know, standard quality electronic components are designed to withstand this heat, without getting damaged. Otherwise, your videos are very informative and useful. Thank you.
absolutely perfect dear
at factory the soldering temperature and soldering time are predefined and set properly, either for manual soldering or automatic soldering
but in the field there is no temperature controlled seldering iron and not too expert soldering person
even in my department my subordinate engineers and technicians most of time damage ics by unconcontrolled temperature soldering iron and soldering time, and in line soldering
so in my experience it is best idea to solder or desolder randomly
please accept my best regards and special thanks for your kind observation
Great video! The old IC you pulled out looked counterfeit. The shape of Texas was more fat and round and the "I" was not clear. The new one that you installed had a definite clear shape of Texas with a definitive letter "I". Thanks for sharing sir!
best regards
most of time the ics have logos but these are not real
as most of the components are being manufactured in china, so brand and quality cannot be certified
just part number is printed
Thank you !!! Best wishes from Turkey
most welcome
Nice to meet you, my name is NEKO🐱TAROU, a Japanese TH-camr. I have the same PSU as you. When it breaks down, I will watch your video and try to fix it. Thank you for sharing the video. 👍
I subscribed to your channel. ❗
most welcome
try to troubleshoot and if you find some difficulty. please let me know. i will try my best to sort out the problem
wishing you best of luck and success
I did enjoy the video. I like how you start off with a careful visual inspection of the components and then zero in on the likely culprits. A very satisfying repair.
Hi Sir, thank you for sharing your knowledge and skills about electronics troubleshooting and repairing, many people who are interested in electronics like me have learned from your videos. I learned a lot from your tutorial videos. In fact I really understood very well how a SMPS woks. Keep up the good work and looking forward to the next tutorial video. More power to you sir. Mabuhay....
Gday great presentation. Liked how you made sure other components were in good shape before replacing the IC. I always learn something from you.
best regards and special thanks
very interesting haseeb thankyou
Hi i love every single video you have produced. Always learn something new. But i am missing something is it possible you can show us how to verify and check components like the rectifiers, small round capacitors, and transistors in and out of circuit. maybe resistors as well.And show us what a good reading should be and what is a bad reading is thanks.
You explain things so good. And you are good at what you do. Thank you for taking time and making this video. Tbark Allah 3alik.
thanks a lot
stay blessed
I love watching your tutorial
video, very helpful. Explanation is very clear. Thank you Sir!
most welcome and special thanks
Sir, thank you for the IC soldering sequence tip.
it is my pleasure
Hello sir , I love to watch and relearn from your vdos , your tip to desolder ICs in random order reminded me of my service instructor who use to reiterate the same thing and i used to repeat to my students .... Best regards
Thank you !!! Best wishes from Brazil 👏👏
best regards 💕
Wonderful video dear friend, have a happy Thursday ☺️
best regards and stay blessed
great tip on soldering IC's
it is my pleasure
You da man, keep the videos coming. Very educational
Hello Mr Haseeb, my youtube teacher. I can watch your videos for hours and not tire, I have a question for you. Do you have a video that can teach us your youtube students how to follow traces from point to point from the various components on a PCB on different types of electronics, or can you make a video for us please, I am trying to learn but I get lost looking at all the lines and most times it is a bit frustrating for a beginner like me because I really want to understand where these traces from each component begin and end and I get lost, thank you teacher for being so professional in the way you teach us!
Was a wear problem of tl494
Because it was oscillating and you got some dc voltages on output.
Also you got voltage near 5 volt in 5 volt referance pin
So If that crack was not exsist the ic would be the last component you suspect to damage
no
it was TL494 failure
initial low voltage are being provided from start up circuit, it is composed of using mosfet gate biasing circuit + pulse transformer secondary side.
this start up circuit, operates the mosfets in conduction state, which cause a limited current in mosfets and the transformer, in result the limited current causes to produce low voltage, and also it provides vcc voltage to SMPS controller, and it can start IC, then ic will start to produce rated output and it starts voltage regulation
Thank you, i have a very similar SMPS but instead of TL494 it has KA7500BD, but i had the same voltage and the same problem. Thanks!
I really appreciate your very detailed and accurate explanation. Many thanks dear .
Can we check the vcc voltage without the ic ( before replacing the new ic) pls ?
Beautiful Video Big Thumbs Up # 532
best regards and special thanks
Very nicely explained and demonstrated
best regards and special thanks
Sir, perfect working in all respects.more over cleaning, very best, and checked each and every transistor, ic , capacitor etc,super job done.thorurouly repaired sir, the best, good 👍
best regards
My dear Brother, I am now only 68yrs! Electronics is my hobby and for passing my liesure period! I fond of watching yours knowledgeable and informative videos like this in You Tube ! May.i expect a little but important help from you? I tried to make a transformer less circuit for 12volt to run a cooling fan (3"12v) with that ? But I have failed! Out put is coming 13.2volt DC ? But while I connect to load the volt shows 4.3 or less! resulting fan is moving very slow! I can't understand what is fault are there ! May be for low ampere or any other reason? I wd like to let you know there are no sufficient room to fix the SD transformer. Kindly help me to give a fruitful suggestion in this regard? I shall be highly grateful to you. My heartiest good wishes for all of your upcoming videos as well as your present video. Stay happy and good bye for the day. I will be awaiting for your reply.
Good afternoon sir.
when you are using 3" 12V fan, it means it is DC fan. it needs more ameres and the transformerless power supply (volatge dropper circuit) can provide just in milliampers, that is causing to drop the volatge to 4.3 volt.
it is better to use isolated transfomre based power supply having a safe limit for current capacity
please accept my best regards
Very Interesting ,,,,,,, Good Teacher......Easy to understand.........Dear Sir ....What is best Bulb wattage for use series to power up MPCS to check....I mean 100w or 40W
best regards
50watt tungsten lamp is awesome for power supplies upto 100 watt.
60/100 watt lamp will good for 100-200 watt power supplies
Salaam Bhai Sahib
wa alaikum salaam bhai Ji
Very good and useful information sir thanks for sharing this knowledge to us
it is my pleasure
Also do we get equal base bias voltage to the main 2 transistors in the start up section when there is no load ? pls clarify . Thanks
Another excellent repair
it is my pleasure
تشکر وسپاس جناب مهندس ممنون وهزاران لایک.....لطفا وحتما راجعب پمپ...و.. وکیوم وهویه مکنده لحیم
وات ان توضیح دهید ممنونم..🙏🙏👌👌❤❤
Thank you for your video. I looked up the TL494 IC chip. I realized that I did not understand it's operation. Is it possible to trouble shoot a circuit like a power supply without totally understanding the operation of the circuit, but able to understand the basics of the circuit operation. For example, I know that the TL494 is the regulator IC. The crack on the TL494 would make you suspect that it is bad. I understand SMPS basics, but I don't totally understand the circuit operation. So, I consider this a learning challenge to understand how all of this works. If someone wanted me to fix a power supply. I probably would spend more time trying to understand how the circuit works than actually spending time on trouble shooting the circuit. Could you suggest any books or material that goes into the circuit operation of power supplies. Thank you again.
Woow before you disassemble it i was thinking that the feedback is in problem thank you
yes brother
everyday we have to learn something new
Do we use of a IC socket for the TL494 ?
Thanks.you explain very good.
اشكرك
I have a quick question. Is that pull the required ampere output such as 20A or 30A or 40A from 230v with a 6A/10A 3 pin? I am using a car amplifier at home which is maximum ampere rated as 35. To get a desired ampere output what should I do?
Well done again 👍
Informative vedeo thank u so much.
it is my pleasure
Haseeb, excellent video with great advice on how to desolder IC's. I was wondering why you needed to take the heat sinks off to do the testing??? Is there a way to test the transistors without desoldering them?
Not that is reliable.
Very nice repair video !!
best regards and special thanks
I have the same problem, but mine is a computer power supply. thank you for the tricks given, maybe I also need to replace the pwm IC.
Very informative thank u so much👌🏼
it is my pleasure
I really enjoy your videos. Thank you.
So nice of you
I want to use smps for my garden lighting supply instead of AC for safety reasons. Will it be a good idea? I will run many 12v DC led bulbs.
Also please tell why SMPS have many output connections? Should I club all connections into 1 set of 12v DC?
Also please tell is there any chance that a SMPS gives AC output and give shock to anyone in the garden?
If there is a chance, what to do? Should I use a fuse to avoid any mis-happening or is there any other method such as MCB?
If yes, what should be the specifications of the fuse/mcb or other component?
Very helpful video. Thanks for this video sir jee
best regards and special thanks
Jazakallahu khairan Bhai 🙏
best regards
Vary very nice video sir
thanks a lot brother
You are good.would like you to so sort out more on inverter problems.
really enjoyed sir soldering/desoldering technique is useful
best regards and special thanks
Good job.....thanks 👍
best regards 💕
Hi sir. Thanks for the videos.
I don't understand how a bad ic tl494 can have its vcc input lowered. I thought the vcc will not affected.
best regards
i think its internal regulator is damaged, which caused to pull down the vcc pin. so ic cannot start working
@@HaseebElectronics thank you very much.
amazing my favorite teacher.
best regards
Very nice, 🌹thanks
Welcome 😊
Hi Haseeb
Can you make a video on the functions of an led/lcd tv t-icon board and how it function.
Thanks on advance
Great love it
Hi Sir. Another excellent repair. Is there any reason for the soldering sequence of the IC? Is it better to solder pins opposite than side by side for overheating? Kind regards, Frederic.
it is best way to divide ic pins in four portions
for example i have 16 pin ic
first i will solder pin 1, then 5, then 9 and 13
then 2, 6, 10 & 14
then 3, 7, 10 & 15
at ast 4, 8, 12 & 16
so using this technique every last pin will get adequate cooling time
Hi sir...namaskaar.
I like your working style.
Which liquid is using to clean the pcb..?
Thank you for the video. Good night 🙏
best regards and special thanks
it is isopropyl alcohol
technical alcohol or methylated spirit
@@HaseebElectronics Thank you for your reply 🙏
Thx so much
جزاك الله خير
االله يسلمك و يسعدك
dear i am watch your video nicely explanation please let me know how aux supply of Control IC is getting
Very good video. How warm are your soldering irons in this video?
i use soldering iron at 380-410 degree centigrade
desoldering tool 420-440 degree centigrade
hi bro salaam, what are the components to buy for starting psu repair
Thanks a lot........👏👍
best regards and special thanks
Very good sir
it is my pleasure
Hi sir which mosfet are used in the smps for ic tl494
Great! What liquid do you use to clean the board with the toothbrush? Thanks
it is
technical alcohol
isopropyl alcohol
or methylated spirit
Bravissimo.
Thanks!
Thanks a lot for your valuable support 💕
Hello
After repairing this type, I noticed that there was a voltage value on the body of the charger that reached 100 volts, when placing the avometer sensors between one of the electrical inputs and the body of the charger.
Is there any clarification because I noticed this using my initial electric screwdriver, which gave strong lighting
Note dear sir
The board and all elements are completely isolated, the sequence lamp does not work, and the device works well after replacing the 13007 transistors
please check this video and reply the results
th-cam.com/video/6c7XCBITZDo/w-d-xo.html
Hi
Very Nice
Thanks
Great ❤❤❤
Hvala za prijevod
zadovoljstvo mi je. ugodan dan
what makes you choose aneng Q1 multimeter instead of the fluke you used previously?
wow great question
I have fluke 179
fluke 115
fluke 77iii
aneng Q1
uni-t ut202a+
and tenma
but I prefer aneng Q1 as it is cheaper, and better response and accurate results
so It attracts me. otherwise there is nothing special behind it's usage
Mashalla, thanks for the videos
best regards 💕
hi sir can we identify the output voltage of smps by the output capacitor for example 1000uf/35 it is possible 24 volts output?
Great video
it is my pleasure
Thank you Haseeb for the great explanation as usual, how can i get the soldering iron tool like yours in this video? and also how can i get the schematic diagram for any smps?
best regards
it is WELLER WR3M made in Germany, you can purchase it online
drive.google.com/file/d/1_gw2TujAWDSzaWYBIpBEOreGime8hKCv/view?usp=share_link
drive.google.com/drive/folders/1TlHNmTDtY2NvDAg1XQUkMQFXhpG3aLuV?usp=share_link
Very impressive
best regards
that was perfect❤❤
thanks a lot
Amazing sir
most welcome
Well done 👏✔👍👌
best regards
Hello 👍👍 thanks you, good man
best regards
Thanks sir.
best regards and special thanks
I did enjoy the video
thanks a lot
Very good teaching
Sir ek Tdk sws 75-24 power supply k out put ma 24 k bajay 5v atay hain aur VR no effect and voltage decreases gradually 24 to 5v kindly what is the fault please
Hi Mr.Haseeb,
my 120W (12v 10A) smps output voltage good but output current very low, i am unable to use 12v 5A load even in smps no voltage fluctuation or down very stable voltage, i checked all components are good in pcb, but low output current, so what is problem & what component to be replace in smps ? waiting your reply
thanks master!
may i ask if AM22a can be replaced by Viper22a?
if we compare datasheets
viper22a and AM22A have same switching frequency of 60KHz
the difference is in VCC voltages. i think AM22A will not work properly in place of viper22a.
as i never did it practically, so i cannot some authentic words
@@HaseebElectronics thanks for ur effort to verify my modification
Good day sir , please can you do a video on how to calculate the output inductor of power supply using tl494 please.
Very nice....
best regards
Thank you my friend, do you have a diagram for this type of power source, because I need some resistor values
kindly check this diagram. might be it may help bit.ly/3y9RJ4g
@@HaseebElectronics Thank you, dear brother. Is this diagram for this particular model, or is there a difference because I will rely on it to read the resistor numbers and replace them with the same value?
MashAllah great
الحمد للہ
Hello Sir! I have a question, how can I change the 5v charger to 12v? If you have time, answer me or show us please!. I saw a video made on TH-cam but I don't know the language, it's mostly indie!
Nice sharing
thanks a lot
I watched most of ur videos .. ur explanation is amazing .. I wish you were my teacher at the University 😁
best regards and special thanks
Thanks.
best regards
Tadh desoldering pump bhout asha lagya
Aslmuailkum lk dn
wa alaikum salaam dear sister
thanks a lot
What did the IC fail ?. The Ic seemed to be cracked and there was discolouration near one pin . This suggested the IC suffered some catastrophic event causing the failure . But no other fault was found , which leaves the question what caused the catastrophic failure of the IC ?
material failure is possible in electronics. as its seems that its reference regulator circuit got problem which caused to chip substrate damage. it is also strange for me that vcc section is normal, and output side of refrence circuit is good
as these 5 vlt reference are being used for chip biasing, internal flip-flops, comparators biasing,
any internal failure may be a reason of its failure
Can you please explain how current control works ?