Very nice! At first you've just bypassed the PFC section and let the SMPS work completely without it right? That way you could identify 24V at the output.
Yes, exactly first i verified, standby section then secondary section at last PFC section in some power supplies, secondary stage is interlocked from PFC, first PFC must turn on and then secondary section will work. in that power supplies, first we need to operate PFC and then secondary will run
I recently watched your video about feedback , I learned a lot. Can you make a video on how to measure secondary voltage when SMPS have standardby circuit and I will also like to learn how does an SMPS with standardby and main circuit work with eachother.
Actually 6.3 ampere is approximately 150% of the actual current. We can say the system peak current with full load will 4 ampere. Without load might be in milliamps (less then 0.25 ampere approximately)
no if pfc circuit is out. when the line voltage will drop less than 200v ac rms approximately. this board will turn off. because it's smps controller needs regulated DC voltage at 400 volt
When you removed the PFC FETs and DIode , did you have to add link on the PCB across PFC output diode holes to connect the bridge output to the large filter capacitor ?
this power supply have 2 rectifiers, d2 (single diode) for coupling supply voltage to the capacitor in parallel there is PFC circuit which have 2 mosfets, and D3 diode. d2 & D3 are connected to same point at capacitor +ve terminal
awesome video dear haseeb sir, i have a problem, one of smps has tvs diode on pfc section, i replaced mosfet that was short ,the short on gate drain caused gate resistor to shift value i removed that as well but now i dont have tvs diode, i tried it without tvs diode and mosfet shorted once again, can you tell me if we can use RCD instead of tvs on pfc section?
Hi! Maybe someone can help me with my ILPI-263 SMPS from my HP monitor. It had a blown rectifier diode in the secondary circuit that i replaced. The monitor is now working fine with on a variable transformer from around 120 - 200 V. When reaching 230 V (standard in europe) the diode blows. Do you have an idea what could be the problem? I am totally clueless at the moment. Thanks
Very good video . What was the root cause of this fault . Often we see with power supplies one fault that then leads to a number of other related failures . So it very interesting at the end to describe what the root cause of the fault was and how it lead to the other secondary failures . Also I was not able to see the Vcc resistor on the schematic . How is the Vcc supply generated after initial turn on of the PFC circuit ? Many good debug techniques demonstrated !
i think it was failure of the MOSFET, which damaged the gate resistors, fuse because (both mosfets in PFC section are in parallel, one of them get short circuited) which caused to all damages
Hi Haseeb, greetings from UK! 😊 So glad I found your channel, you have one of the best teaching styles, clear, calm and concise with practical demonstrations and clear circuit diagrams. I have some electronics knowledge but am looking to build on this and your channel will help immensely! Thanks to this video, I finally grasped the intricate circuitry of the PFC PWM controller! Thank you and have a great day! 😊
Sir, knowledge is power 😊 Vidya danam sarva danal pradhanam". There is no death for good knowledge, think and do, you showed with practical mixed with knowledge, you used brains Sir, with out uttering any thing you could repair 😊but for us you explained, thankyou sir 😊
sometimes it shows resistance but there is no authentication for any resistance value if it gives continuity, then it will short circuit otherwise its functional check will the final serviceability check
@@HaseebElectronics thank you friend, unfortunately it turns out that there is a broken line to the ic, after buying a new one I tried the old ic it was still working, 0.5mm the broken line, seeing the track and signs of burning or checking is indeed an important first step before deciding on a component damaged, blessings are always for learning and always healthy my friend. greetings from Indonesia.
Thank you Sir for this very informative video. But if the series lamp is fluctuating on and off without the pson command and the voltage on the bulk capacitor is fluctuating drastically. Does this imply theres a problem with the input section?
Good video sir, it shows some tests that I learned from you in previous videos and applied when diagnosing a car battery charger of mine which was blowing the fuse. The culprit in that case was 2SK3548 900V, N-Channel Power MOSFET - Fuji, package TO-3P on the primary side of the battery charger. Is the pinout always gate, drain, source from left to right for a similar MOSFET? I have noticed that sometimes a full bridge rectifier is before a transformer and in other cases after the transformer in the circuit. Why is that and what is the difference? The battery charger I have is Anjing AJ-618A, I have been looking for a circuit diagram for months and I can not find it. I have circuit diagrams for the MOSFET and for the IC 3842B, additional code on it is XBLQ but they are quite different from the circuit in the battery charger. I want a circuit diagram for this specific car battery charger for the next time I abuse it and need to repair it. Is someone here that knows where to find it if it exists online?
Sir mere pass harman kardon avr1700 5.1 music system hai system on hota hai pr amplifier section pr supply 45+45- ki dual supply on nahi ho Rahi please help
Hi Haseeb, quick question unrelated to they power supply even though it could apply to some of your repairs, how do you remove potting compounds from circuit boards? I have an inverter which is encased in potting compound I tried using heat from a hot air gun which works but it remove the surface mount components at the same time so it no good especially since I dont have a circuit diagram so dont know what components were blown off and from where
