Σε ευχαριστώ Κωνσταντίνε για την εξαιρετική δουλειά που έχεις κάνει για να μας διαφωτίσεις για αυτά τα τροφοδοτικά! Τα χρησιμοποιώ παρα πολύ στους 3D εκτυπωτές
Thank you very much for this great teardown! Could you please elaborate a little further on the placement of L2 (26:29)? I did not understand the reasoning why it reduces the switching noise better than on the hot side. From the schematic it looks like the situation would be symmetric, as the inductor inhibits current flow for fast switching signals in any case. The only difference seems to be that C24 can short-circuit to PE the switching noise coupled through the main transformer unperturbed, but this capacitor could be placed differently, if L2 was on the HV.
Hello, Thankyou ! I didn't said it reduces Electrical noise on the Output, I said with this arrangement the Radiated EMI to surrounding components is reduced. I also gave a lot of thought why they put it there and in my opinion it is because if it was on the hot Side after the MUR3060PT/PA Diodes Bridge, it would induce Noise into the MUR3060PT Diodes and the Diodes themselves (having the Cathode at the Cooling Tab) capacitive coupled to the Case via the Cooling Pad. Instead now the MUR3060PT Cathodes are directly connected to the Smoothing Capacitors and have more or less a DC Voltage on it instead of Large Pulsing. That's my only logical explanation. I saw it done on other CHINA PSU's too of similar Build but instead of a Bridge they had a 2x MBR30100PT double Diodes in Parallel.
@@KonstantinGrigoriadis Thank you very much for the explanation! I totally forgot to consider a possible effect of capacitive coupling to the heatsink!
Very nice of you to share the schematics, thanks. Just wondering, I can't really understand the current feedback and regulation - looks like the voltage on p15 of TL494 is negative toward GNDS (because the way of the shunt(b) is connected). Seems it's compensated with positive from Vref, but this means when load current is increased, voltage (as you wrote 0.0077 for 1.6A) on p15 is decreased - meaning positive feedback. Can you explain this please?
Hi Alessandro, Thankyou! The Tl494 is not TotemPole it has Diccrete Transistor Outputs. The TL598 is a 1:1 replacement with a TotemPole Output that is a lot Better but still ancient. For new Designs for PushPull and Half/Full Bridge I would use the UCC3808 series From TI, even though more restricted in means of Error Amplifiers , but with a Cycle by Cycle Current Limmiting. Cheers, Konstantin
Maybe they put that filtering inductor on ground side because of lower requirements. I mean, on HV side they probably had to use better part (insulated) and/or move it away from other grounded parts.
As I said , I do Reverse Engineer the PSU, trace the Tracks components and connections of the PCB Board, draw the schematic on Paper fist and after if all looks ok i draw it in Cad. This takes from Hours to Days !
? Its Fully Voltage and Current regulated ! Voltage Feedback goes to Pin 1 and Current Feedback goes to Pin 15 of the TL494... Through Circuitry of course
@@sanjikaneki6226 :-) the Regulation Circuity is Secondary referenced bcs it uses Isolated Gate Driving, a GDT(Gate Drive Transformer), If the Drivers would not be Isolated then Optocoupler Isolation would be used. No Feedback / Auxiliary windings, are mostly used in Offline Flyback Converters and these are to Power the Controller Chip also.
Hello, I Have but its Private. You can ask me on youtube or you ca contact me via email, my email is in my Channel Description. Click on my channel description that ends with ">" or "...more" to open the About section. Cheers, Konstantin
Kalispera k efraristo gia ta kala Logia. Ean k den pistevo oti exo ftasi kan konta sto know how on electronics pou th ithela, to journey arxise me 13xronon ftiaxnontqs piratikous sta fm k mesea stin thessniki ton 70‘s . Likio, politexnio se pliroforiki stin Austriak apo tote exo na kano r&d sta electronics mexri peripou 1995 apo tote sta network design k cybersecurity k aPo to 2014 paralila xana electronics prototyping k design mexri tora. Pola pou ematha itan stin arci self teached . Xeretismata
Hello, Yes, Click on my channel description that ends with ">" or "...more" to open the About section, there you can find my Email. Contact me via Email to send you the Schematic. IMPORTANT! Use only a desktop browser!, seems that youtube on a mobile does not show the email Address for "security reasons"!
Hello, Thankyou, if i would make that video 10-15 min only, either I had to omit lot of Information’s or I had to split it in 2 Videos. Same with all my Longer Videos
Σε ευχαριστώ Κωνσταντίνε για την εξαιρετική δουλειά που έχεις κάνει για να μας διαφωτίσεις για αυτά τα τροφοδοτικά! Τα χρησιμοποιώ παρα πολύ στους 3D εκτυπωτές
Efxaristo poli !
Thank you very much for this great teardown! Could you please elaborate a little further on the placement of L2 (26:29)? I did not understand the reasoning why it reduces the switching noise better than on the hot side. From the schematic it looks like the situation would be symmetric, as the inductor inhibits current flow for fast switching signals in any case. The only difference seems to be that C24 can short-circuit to PE the switching noise coupled through the main transformer unperturbed, but this capacitor could be placed differently, if L2 was on the HV.
Hello, Thankyou !
I didn't said it reduces Electrical noise on the Output, I said with this arrangement the Radiated EMI to surrounding components is reduced.
I also gave a lot of thought why they put it there and in my opinion it is because if it was on the hot Side after the MUR3060PT/PA Diodes Bridge,
it would induce Noise into the MUR3060PT Diodes and the Diodes themselves (having the Cathode at the Cooling Tab) capacitive coupled to the Case via the Cooling Pad. Instead now the MUR3060PT Cathodes are directly connected to the Smoothing Capacitors and have more or less a DC Voltage on it instead of Large Pulsing.
That's my only logical explanation. I saw it done on other CHINA PSU's too of similar Build but instead of a Bridge they had a 2x MBR30100PT double Diodes in Parallel.
@@KonstantinGrigoriadis Thank you very much for the explanation! I totally forgot to consider a possible effect of capacitive coupling to the heatsink!
Your description made it easy to understand the design.
Thankyou !!
Very nice of you to share the schematics, thanks. Just wondering, I can't really understand the current feedback and regulation - looks like the voltage on p15 of TL494 is negative toward GNDS (because the way of the shunt(b) is connected). Seems it's compensated with positive from Vref, but this means when load current is increased, voltage (as you wrote 0.0077 for 1.6A) on p15 is decreased - meaning positive feedback. Can you explain this please?
Thankyou, I have planned a Video on the Subject, Cheers, Konstantin
Thanks for the content. Great. Question: what modern IC would you use in place of the old totem pole driver ?
Hi Alessandro, Thankyou! The Tl494 is not TotemPole it has Diccrete Transistor Outputs. The TL598 is a 1:1 replacement with a TotemPole Output that is a lot Better but still ancient. For new Designs for PushPull and Half/Full Bridge I would use the UCC3808 series From TI, even though more restricted in means of Error Amplifiers , but with a Cycle by Cycle Current Limmiting.
Cheers, Konstantin
As always, good explanation of how it works 👍
Hi Bjorn, Thankyou !
Great presentation and circuit explanation!
Hello, Thankyou very much !
Nice and perfect video, thank you for sharing, please can I have the complet schematic if it's possible.
Thankyou, Yes please send me an Email to reply you with the Schematic.
Hi, I did not received an Email from you yet(To reply you with the Schematic), my email is in the description Page of my Channel.
Thanks mr for sharing knowledge
Good luck👍👍👌👌
Thankyou !!
Maybe they put that filtering inductor on ground side because of lower requirements. I mean, on HV side they probably had to use better part (insulated) and/or move it away from other grounded parts.
Hi, the Output Inductor is placed in the Return Path on the low voltage Output models too.
PLEASE send links for downloading the schematic in both PDF and CAD format.
Hi Paul, Please Contact me via Email to send you the PDF Schematic. Cheers, Konstantin
Thanks & Good luck 👍
Thankyou
How are you making the drawing?
(The program AND method of going from the components on the PCB to the drawing)
As I said , I do Reverse Engineer the PSU, trace the Tracks components and connections of the PCB Board, draw the schematic on Paper fist and after if all looks ok i draw it in Cad. This takes from Hours to Days !
Thank you for sharing.
My pleasure!
Do you think the NTC not enough to safely limit the inrush current?
Hello, The NTC is enough to limit the slow Inrush Current to a safe Level, but not for a instant Short.
Pls add pdf of schematic in description. Thanks
Hello, send me a mail to reply you with the schematic.
Please send schematic for me..
regs2in@gmail.com
Thank you
I have mod only voltage control..
The pcb is different between cv and cv/cc control models of this powrr supply
i dont see how the FB works... or is it just unregulated output?
? Its Fully Voltage and Current regulated ! Voltage Feedback goes to Pin 1 and Current Feedback goes to Pin 15 of the TL494... Through Circuitry of course
@@KonstantinGrigoriadis well i didnt see another FB winding or an optocoupler and that got me a bit confused...
@@sanjikaneki6226 :-) the Regulation Circuity is Secondary referenced bcs it uses Isolated Gate Driving, a GDT(Gate Drive Transformer), If the Drivers would not be Isolated then Optocoupler Isolation would be used. No Feedback / Auxiliary windings, are mostly used in Offline Flyback Converters and these are to Power the Controller Chip also.
thank you , but how did you get the circuit diagram ??
Hello, I fully reverse Engineered the Power Supply!
@@KonstantinGrigoriadis
Excuse me, do you have a Facebook page because I need to ask a question about this topic?
Hello, I Have but its Private. You can ask me on youtube or you ca contact me via email, my email is in my Channel Description.
Click on my channel description that ends with ">" or "...more" to open the About section. Cheers, Konstantin
do you have circuits diagram for linear power supplies ??@@KonstantinGrigoriadis
Which ones ?
How can i use mcp4725 dac module for control output voltage ?
Hello, yes this can be done by using the dac 0-5v output instead of the 10k VTR potentiometer, cheers
@@KonstantinGrigoriadis thanks a lot 🌹💖
Tem o arquivo esquematico pra baixar em pdf?
Hello,contact me via Email to send you the Schematic. Cheers, Konstantin
thanks 👍
Thankyou!
κ. Κωνσταντίνε πως μπορώ να μάθω τόσο καλά ηλεκτρονικά όπως εσείς? Πώς ξεκινήσατε εσείς να μαθαίνετε μόνος σας ηλεκτρονικά?
Ευχαριστώ εκ των προτέρων
Kalispera k efraristo gia ta kala Logia. Ean k den pistevo oti exo ftasi kan konta sto know how on electronics pou th ithela, to journey arxise me 13xronon ftiaxnontqs piratikous sta fm k mesea stin thessniki ton 70‘s . Likio, politexnio se pliroforiki stin Austriak apo tote exo na kano r&d sta electronics mexri peripou 1995 apo tote sta network design k cybersecurity k aPo to 2014 paralila xana electronics prototyping k design mexri tora. Pola pou ematha itan stin arci self teached . Xeretismata
Super!
Thankyou!
Hehe, I have one of these working. And one of these exploded :-)
A 300v one ?
Можно ли получить схему, спасибо.
Hello, Yes, Click on my channel description that ends with ">" or "...more" to open the About section, there you can find my Email.
Contact me via Email to send you the Schematic.
IMPORTANT! Use only a desktop browser!, seems that youtube on a mobile does not show the email Address for "security reasons"!
@@KonstantinGrigoriadis Спасибо, написал на почту.
i wish if your videos be 10-15 minutes . againe thanks too much
Hello, Thankyou, if i would make that video 10-15 min only, either I had to omit lot of Information’s or I had to split it in 2 Videos. Same with all my Longer Videos
👍👍👍👍👍
Thankyou !!!
@@KonstantinGrigoriadis👋😊
Good job, but don't remove the shirt 😀
Thankyou !! But what you mean ? :-)
👋👋😊
Thankyou!