Well.... no look at the RDSon of them when she is messuring them 0,7 Ohm! if she put there 15Amps there will be power loss almost 80 W on each tranzistor. They would burn instantly
The input voltage range is up to 30v this means that if the ic switch to the ground (pin 8,11) between G-D the tension is higher then the maximum 20v this kill the MOSFET
The supply is unstable. when you show the scope waveform at 2:32 the pulses are dithering with a 10 Amp load. If you reduce the load to just a few amps it may get worse.. You cannot use the DVM to check for stability. The output could be oscillating from 0 to 10V and the DVM will show 5V. The scope is the only way and the pulses must be completely steady. In any case I give this a Thumbs UP!
Great video. Recently, there are many options of good PWM controller. One of them is RT9259 which applies totem pole output state. Totem pole output can prevent voltage-pumping by complex load. Cheers from Indonesia
Yes, No Word To Say For Your Excellance, it is a perfect working also i made this and create some of changes for protact high voltage from input output side make a fix voltage with register and zener and fix amp for charge the battery like a mppt and put one more protaction for cut the battery current from 10% charge amps to 1% when battery voltage rise 14.2 till 14.4 charge with like 0.4 amps i have no any word to say about your expiriance you always make perfect circute with all of calculation and risk fres god bless dear my last feedback for you circute a buck convert a voltage from 15 to 90 volt with 10 amp to 50 amp and protaction of high and low side with lighting protaction revers polarity protaction and display it with i2c input support up to 700 watt low side outside voltage fix 14.4 and 50 amps and it 98% efficiancy support no west energy. in 700 watt minus 2% energy lost max 20 watt of pcb heat and 10 to 15 watt lost of cabble resistance finaly out 45amp need 45x14.4(out)=648 watt for dirext use home load with 750watt pure sine wave inverter 200 amps battery charge on day sun time in 9 hour by 20amps thankes
Hello boss. Pls replay.. i need that circuit. I created with the given circuit but not got sucess .my output is there but no voltage change when changing the pot. What problem pls
Very good video. You explain circuit function very clearly and the visuals outlining the parts of the circuit you are describing the function and operation of is very helpful. Found that modification to the surface mount transistor very interesting too. Thank you and keep up the good work! :)
Ben bu devreyi 0 50 v , 0 10A olarak yaptım, tl494 ü ve kullandığım 16f676 entegresini 12V ile besledim, Devre çok karallı çalıştı, yalnız R9 daki direnç kavlurdu, yine de düzenli çalışıyorlar öneri, Videolarınızda kendi orjinal sesinizi kullanınız, kendi sesiniz daha güzel, Teşekkürler
The current sensing resistor (Rx) is outside of voltage control loop! The output voltage will droop with the voltage drop on this resistor (0.375V). Output voltage will not be stabilized.
I built it & it works ,BUT , as he mentions it's not a bench powersupply ,it's a charger .because it is very noisy . At 3 amps output i get about 2.5 volts of ripple .
I have build this circuit but this circuit diagram does not work until you replace R7 (220R) to R9 (1K) and also completely remove R8 (220R) than it works great
I really appreciate this supply for hobbyist, but in older days I have seen it working from 0-24v. I want you to please mention changes to make it work from 0v level rather than 2v
Thanks for your tutorials,I bought both transformer calculator programs,can you make a video for flyback converter and how to use the application,thanks .
your diagram can not match with your project... say what kind of resistor you used on R9? and its watt and its resistance ? also doubt about R1... and you use mosfet driver as emiter follower why ?
maybe I can use this schematic to turn it into an AM modulator! instead of the voltage regulating potentiometer, I do the modulation in there. the control schematic for stabilization will also be canceled!(does not have to be made!) Friendly greetings from The Netherlands! Rob.
Are you sure that the values of the resistors R7 and R9 are as shown in the schematic? Something seems to be wrong with the driver stage. VT1 seems to be permanently on. This means that it's emitter will always be in almost the entire B+ voltage. This voltage needs to be shorted to the circuit ground when the end of the the R9 terminal that goes to TL494 is grounded through the I.C. Is the value of R9 capable to saturate VT2 and can VT1 (or both transistors) withstand such direct short circuit currents of the power supply voltage, especially if it is at 30 Volts? I wonder how much is the power loss of the driver stage as it is shown. Not the best design anyway.
Hello, i built the circuit but i found out that one of the P channel mosfets is always giving maximum output while the other is regulating. Other thing, the circuit doesn't work with input below 18v and doesn't go more than 11v. Any idea why ? Thanks
@@hichamtassi1753 Since the two mosfets work in parallel, what you say seems to be not possible. If one of them is shorted out, only in this case can this problem happen, but in such a case there is no regulation at all. You need to check your connections again and see the test signals at the output of the I.C. Normally it should work properly with 12V input. Check the 5V voltage reference of the I.C as well...
@@ΠάριςΑζής Hello, i checked and indeed one of the Drain tracks was cutted. Now it regulates the voltage normally. But below 18V it turns off, the current limit function works but max current obtained is 500mA (with 0.02 ohm resistor), and the irf9540 that i used heat a lot even with only 100mA load.. I have also noticed something: in the PCB the drains are linked to the diode whereas in the diagram, the source is linked to the diode, it seems Drain and Source are inverted... Thanks for your comments on this.
@@hichamtassi1753 The drains are correctly connected to the cathodes of the double shottky diode. The sources are connected to B+. This is normal because the mosfets are P channel. The schematic is correct as regards that. You need to find out the fault by careful troubleshooting. Check the resistor values first and their connections afterwards. Then you must do the adjustments of the trimmers...
@@ΠάριςΑζής Ok, thanks for the info on the P channel. The issue i am facing now is that i have no power, voltage adjustment is ok, but under small load, voltage drop to zero regardless of the potentiometer position. Pin 16 sees from 0 to 0.6v, and i traced the shunt, and it seems good. Any idea where to look at ? Thanks
Thank you for the excellent Circuit. Need some help on output Transistor, can you suggest any other transistors equivalent in place of IRF4905 they are not available in our market. My transformer DC output is 37V- 6Amps after filter. I want to use this as bench power supply for my mini workstation. I am a hobbyest.
Thank for the knowledge.. .if you have any idea about how to build a 12-30vdc input and an output of split type psu like +/-50vdc.. .the ampplication why its split type for thw output is for amplifier..
Nice job. This really simplifies the TL494 circuit to a design that is more easy to understand. Someone correct me if I'm wrong please... Most circuits built around this chip are "off-line" topologies (they are connected to mains voltage). If I understand this correctly, the chip has it's maximum input power limitations just like the circuit shown here. When it is connected to a mains powered topology the chip must be powered from an additional auxiliary transformer winding. The mains voltage is far too high to be rectified and connected directly to the chip. So we need a extra way to power the chip and that's an auxiliary winding. Of course, this winding can't power the circuit until the switching action is started. This sucks. How do you get power to the chip when you need the chip to create the power? We need a special start-up circuit that can provide a tiny amount of current through a high value resistor. This is barely enough to kinda 'jump start' the control chip so it can draw extra power from the auxiliary winding and circuit. Additionally, this is a major design limitation. This auxiliary winding and circuit is affected by the switching action of the control chip. So, if the load changes and the controller adjusts the output to compensate, the auxiliary circuit changes as well. This means the auxiliary power circuit must be designed for the correct voltage range of the output. This range is rather small and limited. This is one of the largest factors involved with how high or low a power brick output voltage can be changed or adjusted. By limiting this chip to an input range compatible with the control chip instead of mains power, the need for an isolation transformer with mains auxiliary winding and rectification, along with a start-up circuit are eliminated. Without the isolation transformer the voltage and current feedback circuits don't need the additional complications of a secondary voltage reference (tl431), or optocouplers. This design has greatly simplified this chips basic circuit design to something far easier to understand. I'm still not 100% sure why this needs a P-Channel MOSFET though. Can someone explain (simply) why an N-FET won't work? Thanks for the upload. -Jake PS (to my former, even more ignorant, self): The TL494 is also cloned and called a KA7500. These chips are very common inside old computer power supplies, and lots of circuits with medium power output levels between 1 to 10 amps. I have pulled them from several plug in car chargers with output currents larger than 1 amp, car audio amplifiers, and ATX computer power supplies. They are also dirt cheap directly from China :-)
The first part is correct. You can use a small mains transformer to power the chip separately. This also gives you the opportunity to use a gate drive transformer and have direct feedback since the chip will be on the secondary side. the P channel is used because it's easier to drive without a high side driver. In the buck converter, the Mosfet's source is not connected to ground, so you need a bootstrap circuit to drive it from the chip. This is typically done by a specialized chip such as IR2110/IR2101/IR2108.
In this video there is a Chinese type power supply similar to the baku 1502 but you can see an LCD display inside... What modification did you make? What circuit is inside? schematics of this Thank you
Hello! I have made this circuit according to the diagram, but I can only adjust the output voltage in the range of 2-13vdc while the input voltage is 24vdc. Please show me why?
Hello, Thanks so much for the video. I'm wondering how could I modify the schematic to get 0-60VDC, 0-50A adjustable output? Can you help me with that?
Through the actual production, when the input voltage above 27 v, output voltage is close to the output voltage, power tube will be destroyed. Test conditions for no-load cases, could you tell me what is the cause, thank you.
I have made this and every parts inclouding voltage and cureent setting working fine But short circuit protection dident work By the way i install 0.05 shunt So why short circuit protection wont work???
Mind blown on re-packing the transistor!
Well.... no look at the RDSon of them when she is messuring them 0,7 Ohm! if she put there 15Amps there will be power loss almost 80 W on each tranzistor. They would burn instantly
@@electronicpower1826she is only the narrator for english 😃
Who made the video i think is a slavic probably russian man 🫡
@@Norbydaner looks Like it 😂
Da best explanation of TL494.
Simple and clear. You make hard stuff became easy stuff to explain.
Broke TO220, to new part. You are awesome, man.
What a great video, very impressive, I have no words to describe
MY FAVOURITE Channel KASYAN TV.
I need circuit diagram
The interference ( 15:29 ) is actuality coming from the power supply itself. This is a Switch Mode Power Supply (SMPS) , they produce a lot of noise.
The long awaited and searched video, thanks
A clear example of Chip Surgery :) good video!
I love the ingenuity, I did something similar with smt ics.
Great Video!
This is a Buck Converter build for those of you that were looking for a Boost converter.
I was looking for a Boost converter. Lol
The input voltage range is up to 30v this means that if the ic switch to the ground (pin 8,11) between G-D the tension is higher then the maximum 20v this kill the MOSFET
I noticed that, was going to comment.
Zener diode is a must
It is possible to use n chanel mosfet using charge-pump capacitor
Attila....new subscriber lol
Correct remark.
Thank you for another excellent video, always the best circuits!
Very good project 👍
The supply is unstable. when you show the scope waveform at 2:32 the pulses are dithering with a 10 Amp load. If you reduce the load to just a few amps it may get worse.. You cannot use the DVM to check for stability. The output could be oscillating from 0 to 10V and the DVM will show 5V. The scope is the only way and the pulses must be completely steady. In any case I give this a Thumbs UP!
Excellent video and a very good presentation. God bless you dear!
Love the Frankentransistor
Great video.
Recently, there are many options of good PWM controller. One of them is RT9259 which applies totem pole output state. Totem pole output can prevent voltage-pumping by complex load.
Cheers from Indonesia
I never such a good explanation about tl494 in youtube, great explanation and can you do how to design circuit with tl494
That app is utterly amazing 😍
In put capasitor are important.and you can add a 100n capasitor at the out put to remove spayks
Yes, No Word To Say For Your Excellance,
it is a perfect working
also i made this
and create some of changes
for protact high voltage from input
output side make a fix
voltage with register and zener and fix amp for charge the battery like a mppt and put one more protaction for cut the battery current from 10% charge amps to 1% when battery voltage rise 14.2 till 14.4 charge with like 0.4 amps
i have no any word to say about your expiriance
you always make perfect circute
with all of calculation and risk fres
god bless dear
my last feedback for you
circute a buck convert a voltage from 15 to 90 volt
with 10 amp to 50 amp
and protaction of high and low side
with lighting protaction
revers polarity protaction
and display it with i2c
input support up to 700 watt
low side outside voltage fix
14.4 and 50 amps and it 98% efficiancy
support no west energy.
in 700 watt minus 2% energy lost max 20 watt of pcb heat
and 10 to 15 watt lost of cabble resistance
finaly out 45amp need
45x14.4(out)=648 watt for dirext use home load with 750watt pure sine wave inverter
200 amps battery
charge on day sun time in 9 hour by 20amps
thankes
Hello boss. Pls replay.. i need that circuit. I created with the given circuit but not got sucess .my output is there but no voltage change when changing the pot. What problem pls
Very good video. You explain circuit function very clearly and the visuals outlining the parts of the circuit you are describing the function and operation of is very helpful. Found that modification to the surface mount transistor very interesting too. Thank you and keep up the good work! :)
Muí bueno ok
Todo bien
Thank you for your videos, it’s very interesting. I learn a lot with you. I encourage you to keep doing interesting videos like this !
Very Nice circuit and explains.
You videos is very good, your explanation is very very good
Wow that was so cool DIY transistors!!!
Ben bu devreyi 0 50 v , 0 10A olarak yaptım, tl494 ü ve kullandığım 16f676 entegresini 12V ile besledim, Devre çok karallı çalıştı,
yalnız R9 daki direnç kavlurdu, yine de düzenli çalışıyorlar
öneri, Videolarınızda kendi orjinal sesinizi kullanınız, kendi sesiniz daha güzel, Teşekkürler
I Made the circuit but MOSFETs get very hot even on low current
The current sensing resistor (Rx) is outside of voltage control loop! The output voltage will droop with the voltage drop on this resistor (0.375V). Output voltage will not be stabilized.
Nice circuit board with great efficiency 👍👍👍👍
I have never seen somebody Hacking a MOSFET before.
Articolo molto interessante, da imitare; peccato non ci siano indicazioni per la costruzione dell'induttanza, ottimo se funziona.
Really nice work, dude! Great little board! 😃
no need pairs of BD transistors ,in this configuration TL494 can comand directly MOS FET 's.
I built it & it works ,BUT , as he mentions it's not a bench powersupply ,it's a charger .because it is very noisy . At 3 amps output i get about 2.5 volts of ripple .
I have build this circuit but this circuit diagram does not work until you replace R7 (220R) to R9 (1K) and also completely remove R8 (220R) than it works great
I made the circuit but it doesn't adjust the voltage and amperes. Can you help me
Thank you. Those changes made my circuit work.
@@victorribeiro2304 can you help me
@@ugurozsoy8001 what's wrong?
@@victorribeiro2304 I did the circuit exactly but it did not work. I cannot control the voltage and amperage.
I really appreciate this supply for hobbyist, but in older days I have seen it working from 0-24v. I want you to please mention changes to make it work from 0v level rather than 2v
Thank you for another excellent video
Thanks for your tutorials,I bought both transformer calculator programs,can you make a video for flyback converter and how to use the application,thanks .
Projetos sempre excelentes
nice product.. please make some device to up the current of solar panels 30wp more.!!
thanks for contribution my friend!
1.98 volt minimum,, not 0,,but i see the great explanation👍 ,,very well
Great xplain, the best.
TKS
your diagram can not match with your project... say what kind of resistor you used on R9? and its watt and its resistance ? also doubt about R1... and you use mosfet driver as emiter follower why ?
Very good video, power supply with circuits electronics
Wow this is crazy , good job
you are a different woman and a different person and so you are so impressive.
Love your videos and channel, need more these types of videos, thanks
Excellent vidéo merci
Por que no hacen una traducción en español en todos sus vídeos gracias
Excelente video.
Hola mi qeridos amigo te invito amo canal si te gusta suscríbete mucha gracias desde REPÚBLICA DOMINICANA
maybe I can use this schematic to turn it into an AM modulator!
instead of the voltage regulating potentiometer, I do the modulation in there.
the control schematic for stabilization will also be canceled!(does not have to be made!)
Friendly greetings from The Netherlands!
Rob.
can you make mppt solar charging controller!
Are you sure that the values of the resistors R7 and R9 are as shown in the schematic? Something seems to be wrong with the driver stage. VT1 seems to be permanently on. This means that it's emitter will always be in almost the entire B+ voltage. This voltage needs to be shorted to the circuit ground when the end of the the R9 terminal that goes to TL494 is grounded through the I.C. Is the value of R9 capable to saturate VT2 and can VT1 (or both transistors) withstand such direct short circuit currents of the power supply voltage, especially if it is at 30 Volts? I wonder how much is the power loss of the driver stage as it is shown. Not the best design anyway.
Hello, i built the circuit but i found out that one of the P channel mosfets is always giving maximum output while the other is regulating. Other thing, the circuit doesn't work with input below 18v and doesn't go more than 11v. Any idea why ? Thanks
@@hichamtassi1753 Since the two mosfets work in parallel, what you say seems to be not possible. If one of them is shorted out, only in this case can this problem happen, but in such a case there is no regulation at all. You need to check your connections again and see the test signals at the output of the I.C. Normally it should work properly with 12V input. Check the 5V voltage reference of the I.C as well...
@@ΠάριςΑζής Hello, i checked and indeed one of the Drain tracks was cutted. Now it regulates the voltage normally. But below 18V it turns off, the current limit function works but max current obtained is 500mA (with 0.02 ohm resistor), and the irf9540 that i used heat a lot even with only 100mA load..
I have also noticed something: in the PCB the drains are linked to the diode whereas in the diagram, the source is linked to the diode, it seems Drain and Source are inverted...
Thanks for your comments on this.
@@hichamtassi1753 The drains are correctly connected to the cathodes of the double shottky diode. The sources are connected to B+. This is normal because the mosfets are P channel. The schematic is correct as regards that. You need to find out the fault by careful troubleshooting. Check the resistor values first and their connections afterwards. Then you must do the adjustments of the trimmers...
@@ΠάριςΑζής Ok, thanks for the info on the P channel. The issue i am facing now is that i have no power, voltage adjustment is ok, but under small load, voltage drop to zero regardless of the potentiometer position. Pin 16 sees from 0 to 0.6v, and i traced the shunt, and it seems good. Any idea where to look at ? Thanks
Thank you for the excellent Circuit. Need some help on output Transistor, can you suggest any other transistors equivalent in place of IRF4905 they are not available in our market. My transformer DC output is 37V- 6Amps after filter. I want to use this as bench power supply for my mini workstation. I am a hobbyest.
Thank you
First like from tamilnadu 😀👍
👌👍
Great video, thanks.
Just like a monster!!
Very good! Another great job,Keep up !
Pcb layout is missing...pls upload...
Very nice voice.
Great stuff as usual. I just want to know how to attach an lcd display to show output values and input values auch as current and voltage.
Very informative...thanks for video
Касьянчик, ты что ли?!))) 👍👍👍
Love your videos thanks
A link to an archive is not working, great video though
По английски стабилизатор будет regulator, не stabilizer. Вообще, над переводом еще стоило бы поработать.
Superb converter
Vey very good, thank you so much.
great project
Make video how to make variable 1 V and 40 A power supply.
Muy interesante, muchas gracias.
Hola mi qeridos amigo te invito ami canal si te gusta suscríbete mucha gracias desde REPÚBLICA DOMINICANA
Thank for the knowledge.. .if you have any idea about how to build a 12-30vdc input and an output of split type psu like +/-50vdc.. .the ampplication why its split type for thw output is for amplifier..
Yes, a split rail is useful for audio amp circuits.
very good video
Nice!!!
Very good
Can you make with CC Constant Current - CV Constant Voltage please
This is cc cv
Hola. Felicidades por el video.una pregunta. Se puede poner un toroide más grande que tenga 80uh igual en vez de poner dos?
How can we use N channel mosfet?
Schematic 220 ohm, you use 150 ohm?
Nice job. This really simplifies the TL494 circuit to a design that is more easy to understand.
Someone correct me if I'm wrong please... Most circuits built around this chip are "off-line" topologies (they are connected to mains voltage). If I understand this correctly, the chip has it's maximum input power limitations just like the circuit shown here. When it is connected to a mains powered topology the chip must be powered from an additional auxiliary transformer winding. The mains voltage is far too high to be rectified and connected directly to the chip. So we need a extra way to power the chip and that's an auxiliary winding. Of course, this winding can't power the circuit until the switching action is started. This sucks. How do you get power to the chip when you need the chip to create the power? We need a special start-up circuit that can provide a tiny amount of current through a high value resistor. This is barely enough to kinda 'jump start' the control chip so it can draw extra power from the auxiliary winding and circuit. Additionally, this is a major design limitation. This auxiliary winding and circuit is affected by the switching action of the control chip. So, if the load changes and the controller adjusts the output to compensate, the auxiliary circuit changes as well. This means the auxiliary power circuit must be designed for the correct voltage range of the output. This range is rather small and limited. This is one of the largest factors involved with how high or low a power brick output voltage can be changed or adjusted. By limiting this chip to an input range compatible with the control chip instead of mains power, the need for an isolation transformer with mains auxiliary winding and rectification, along with a start-up circuit are eliminated. Without the isolation transformer the voltage and current feedback circuits don't need the additional complications of a secondary voltage reference (tl431), or optocouplers. This design has greatly simplified this chips basic circuit design to something far easier to understand.
I'm still not 100% sure why this needs a P-Channel MOSFET though. Can someone explain (simply) why an N-FET won't work?
Thanks for the upload.
-Jake
PS (to my former, even more ignorant, self):
The TL494 is also cloned and called a KA7500. These chips are very common inside old computer power supplies, and lots of circuits with medium power output levels between 1 to 10 amps. I have pulled them from several plug in car chargers with output currents larger than 1 amp, car audio amplifiers, and ATX computer power supplies. They are also dirt cheap directly from China :-)
The first part is correct. You can use a small mains transformer to power the chip separately. This also gives you the opportunity to use a gate drive transformer and have direct feedback since the chip will be on the secondary side.
the P channel is used because it's easier to drive without a high side driver. In the buck converter, the Mosfet's source is not connected to ground, so you need a bootstrap circuit to drive it from the chip. This is typically done by a specialized chip such as IR2110/IR2101/IR2108.
@@BogdanSerban ino
Protect gates with zener
At 1:52, what about the TL494 pin no:3 (feedback)?
Very nice. thanks you too much
In this video there is a Chinese type power supply similar to the baku 1502 but you can see an LCD display inside... What modification did you make? What circuit is inside? schematics of this Thank you
You had me at hacking the P channel lol
Very informative video mam....
Verry good video. But could you show what transformer i schould use if i want from 230v to 28v and how much imputcurrent is required?
Good explain
Thanks
Hello! I have made this circuit according to the diagram, but I can only adjust the output voltage in the range of 2-13vdc while the input voltage is 24vdc. Please show me why?
Pls can u provide me the circuit??
Hello, Thanks so much for the video. I'm wondering how could I modify the schematic to get 0-60VDC, 0-50A adjustable output? Can you help me with that?
Good day sir love the video, But can you help me sir in replacing MBR30100 ? because im using proteus 8 sir.
Como darle.usos a tranformadores de este tipo
Nice video🙂👍, i want to ask. Can i use toroid value above 80uH? Like 100 uH?
You use 2 resistor 0.1 ohm 5w it mean current shunt is 0.05 ohm is that correct ? Can use any P chanel mosfet with high output amps ?
Can you try to build diffrencial power with common components.?
Through the actual production, when the input voltage above 27 v, output voltage is close to the output voltage, power tube will be destroyed. Test conditions for no-load cases, could you tell me what is the cause, thank you.
Can I use it as solar charge controller?
U can
I have made this and every parts inclouding voltage and cureent setting working fine
But short circuit protection dident work
By the way i install 0.05 shunt
So why short circuit protection wont work???
Sir please e rickshaw par banao is ke technician bahut Kam hai