TL494 Pulse Width Modulation Control Circuit

[@HyperspacePirate]

Thanks for the explanation. I've been trying to build a PWM controller by controlling transistor oscillator bias but this is a way simpler solution.

[@AllAmericanFiveRadio]

Thanks and your welcome.

[@skycarl]

Good video Rick. Will be interesting to see it at work in that radio. Thanks for sharing.

[@AllAmericanFiveRadio]

Thanks

[@shvideo1]

Wow a lot of work went into this video. Excellent information on this very useful IC. Thank you for sharing. Really enjoyed the presentation.

[@AllAmericanFiveRadio]

Thanks very much. You maybe interested in this video also. Pulse Width Modulation Half Bridge MOSFET Driver TL494 2N2222 IRF510 kzbin.info/www/bejne/pIWohZWYo5KXn8k

[@shvideo1]

@@AllAmericanFiveRadio Thank you for the suggestion. Will definitely check it out. Keep up the great work.

[@Mike-ry4ti]

Thanks for the video. I have a question- why are driver transistors necissary in the case of driving mosfets? Is the 200mA max current from the internal transistors insufficient to drive them directly? Thanks!

[@AllAmericanFiveRadio]

I am experimenting with a new configuration of this circuit. The output of the TL494 can over lap. Adding transistors changes the phasing 180 degrees so now the overlap is the ground and not the positive pulses. This video shows the new circuit plus a very experimental circuit for HO output. I plain on developing it as one of my winter projects. My email is [e-mail] make the subject TL494. Project: kzbin.info/www/bejne/hpzaoqqBhdN5pqM

[@lt.schlechtnacht9414]

Are you suppose to change both the Capacitor and resistor on RT and CT to change the frequency or just the capacitor

[@AllAmericanFiveRadio]

In the PDF RT = 12K and CT =0.01uF, I would there. www.ti.com/lit/ds/symlink/tl494.pdf I have just changed CT to get the frequency I want. But it maybe necessary to change RT also to get the frequency you want. Use the RC time constant. www.digikey.com/en/resources/conversion-calculators/conversion-calculator-time-constant

[@lt.schlechtnacht9414]

@@AllAmericanFiveRadio wow! Thank you and thank you for posting! very useful information

[@grantpeterson2524]

Incredible video. Been trying to build a circuit with this chip for days, but all of the videos either go into too much detail for me to get anything out of it or just throw a circuit diagram without any info beyond that. Thank you!

[@AllAmericanFiveRadio]

I'm glad this video helped. THANKS! You may like this video. Pulse Width Modulation Half Bridge MOSFET Driver TL494 2N2222 IRF510 kzbin.info/www/bejne/pIWohZWYo5KXn8k

[@MaricuchaVargas-k9b]

Hi, Is it possible to change the duty cycle of EC1 and 2 independently?

[@AllAmericanFiveRadio]

There is nothing labeled EC1 or EC2?

[@ThatElectronicsFool]

Other similar ICs, but probably a bit dated, are the SG3524(and 25). Saw the TL494 used in almost every single switching PC power supply of the past couple decades, at least. Sometimes would see a KA7500. Now days seems they use more advanced stuff, or UC3842(or 43). All these chips definitely helped keep high power PWM supplies simple in design.

[@AllAmericanFiveRadio]

Thanks and thanks for the information

[@HugoMaxMTeixeira]

Muito obrigado, me ajudou muito com algumas dúvidas. Thanks, very good demonstration.

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@standishgeezer]

It would be interesting to know what frequency is delivered in the current layout and what frequency range could be achieved by substituting the 10K resistor on pin 6 with a 10K pot (leaving the 0.01uf as it is on pin 5).

[@AllAmericanFiveRadio]

mustcalculate.com/electronics/rctimeconstant.php Time constant ~100 microseconds Rise time from 20% to 80% 140 microseconds Rise time from 10% to 90% ~220 microseconds 3dB cutoff frequency ~1.591549 kilohertz

[@cnccnc9070]

Would be possible to use the 2 outputs on same frequency/same phase, but adjust duty separate ?

[@AllAmericanFiveRadio]

Yes you could have the output you want drive two transistors and use each as an in phase output.

[@hefnijaber7088]

Kindly I ask you what is type of connection of two potentiometers located in the upper left corner of the circuit ( how I can connect the 3 pins of 1M ohm with 3 pins of 50K ohm) thanks

[@AllAmericanFiveRadio]

The 1M sets the limit, usually a value of about 15K works nicely. The 10K varys the output from the limit to the max. I prefer this setup of the TL494. Unlisted video. kzbin.info/www/bejne/hpzaoqqBhdN5pqM

[@gaboinelectronic.1943]

How about a friend, I would like to know if the output frequency is 50hz and what output oscillation voltage delivers pin 8 and 11 ... greetings.

[@AllAmericanFiveRadio]

Pins 5 & 6 is an RC time constant so just choose the resistor and capacitor for 50kHz.Pins 11 & 8 have pull-up 1k resistors to +12VDC so the output is a little less than +12VDC.

[@hefnijaber7088]

Please I need your help to tell me if there is software I can used it to simulate HFT ( high frequency transformer) thanks

[@AllAmericanFiveRadio]

Simulate HFT, does that mean you want to simulate HFT on a screen like an oscilloscope? Do you want to control the transformer with software? I’m not understanding your question.

[@hefnijaber7088]

@AllAmericanFiveRadio yes I want to simulate HTF on screen like an oscilloscope and I want to presented circuit completely using mutisim program

[@AllAmericanFiveRadio]

@@hefnijaber7088 I just got this comment. Protues didn't show the sine wave Answer: Simulations are limited.

[@Leonardo-eu9rj]

Hi, I see periods of time where both MOSFETs will be turned on simultaneously. Is that correct? What application would have that situation? Thanks for you video!!

[@AllAmericanFiveRadio]

Yes that is correct. One thing you could do would be to adjust your variable resistor so that you get just before any overlap. Measure that resistance and put it in series with your verbal resistor, that way you cannot get into overlap. I did do another video on the subject and I think you'll find it interesting. May give you some more ideas. Pulse Width Modulation Half Bridge MOSFET Driver TL494 2N2222 IRF510 kzbin.info/www/bejne/pIWohZWYo5KXn8k hope this helps

[@hefnijaber7088]

Thanks for your keen efforts done to producing such interesting videos kindly I ask you which software contain HFT (high frequency transformer) because I want to simulate circuit contains tl494 and transformer, frequency for tl494 depend only on on resistor and capacitor value on legs 5&6 best regards

[@AllAmericanFiveRadio]

Yes, the TL494 has a built in oscillator, and the frequency is dependent on the RC time constant on pins 5 and 6, and the variable resistor on pin 3. I prefer the TL494 configuration in my unlisted video. Here is the Link: kzbin.info/www/bejne/hpzaoqqBhdN5pqM

[@doost6233]

I tested this it only works for frequency of about 300hz does not work at 60hz.

[@AllAmericanFiveRadio]

The chip specifications says 1KHz TO 200kHz What are you wanting to make?

[@hefnijaber7088]

Thanks for your keen efforts done by you to produce such interesting videos kindly I ask you is there is high frequency transformer component in any application allow me to make simulation for any circuit contain HFT and TL494, and frequency for tl494 depend only on resistor and capacitor on legs 5&6 best regards

[@theinnovati0nlab782]

Very nice! I am currently working on a high power 5000W synchronous dc to dc boost converter system and I am planning to use TL494 as well. Great video. Success wishes! 👍👍 The Innovati0n Lab💥

[@AllAmericanFiveRadio]

Thank you, and your welcome. This circuit will not produce any usable power. It is for demonstration only. I will be glad to help, and try to answer questions you may have. My email is [e-mail] : make the SUBJECT TL494 project

[@theinnovati0nlab782]

@@AllAmericanFiveRadio Sounds great! I made a video a while ago to introduce my concept - basically my goal is to design a synchronously controlled interleaved boost converter system - capable of delivering high output currents even at low input voltages. If this works, then I will see about modifying the circuit to operate with synchronous rectification - for better efficiency. Texas instruments did a wonderful job with the TL494 datasheet by explaining all the design considerations and calculations....Switching frequency, power inductor selection, dead-time control, filter capacitor selection.....etc. These will be covered in my next video. Thanks again! The Innovation Lab

[@mbashir42]

Thanks for uploading this nice video. It's really helpful. Could you please tell about 10k potentiometer fixed between pins 3 and 4. What's purpose and how it value was adjusted?

[@AllAmericanFiveRadio]

It adjusts the minimum plus width.

[@mbashir42]

Sir many thanks for your reply. Can we use the same circuit and duty ratio adjustment for a single switch converter?

[@Hudsonkem]

which is the oscilation frequency?

[@AllAmericanFiveRadio]

10,000 Resistance 0.01uF Capacitance Time Constant = 0.0001 Frequency = 1,591.5 Hz

[@Hudsonkem]

@@AllAmericanFiveRadio thx im still learning... :)

[@bundylovess]

Hi grate video Big thumbs up. I noticed there was a difference in pulse width between Chanel 1&2 would this be a problem driving a transformer in push pull configuration ? Cheers . Looking forward to seeing this project in action

[@AllAmericanFiveRadio]

I don't think it will be a problem. But we'll find out. Thanks.

[@ELECTROGYAN]

Sir can u tell me the formula for output frequency

[@AllAmericanFiveRadio]

RC frequency calculator www.omnicalculator.com/physics/rc-circuit

[@Dc_tech386]

Yes but the duty cycle won’t step down to increase output volt I did try it and the ac voltage on the transformer dop from 120 to 70 ac the duty’s cycle at 50 % give only half the voltage of anything it driving 39 % of duty cycle put out almost power power on transformer with load

[@AllAmericanFiveRadio]

It all changes and depends on the transformer and frequency used.

[@Edmorbus]

You can find this chip in PC power supply Thanks for sharing

[@AllAmericanFiveRadio]

Just Google TL494

[@Edmorbus]

Thanks

[@biafrafetech1580]

Goody Sir, I want to know if i connect pin 8 and 11 to a high speed mosfet drive and the a mosfet, can i use it to drive a HF transfformer and what could be it friquency?

[@AllAmericanFiveRadio]

I think your idea will work. But you will probably have to drive junction transistors first, and let them drive the MOSFETs. This is because I don't think the chip puts out enough voltage to drive the MOSFETs on all the way.

[@diecksl]

@@AllAmericanFiveRadio The TL494 is very well-know to Tesla Coil and HV enthusiasts for this purpose. Usually the PWM output is fed into MOSFETs or (isolated) gate drivers, for example a chip like the A3120.

[@aminusalisu4657]

thanks for the knowledge you shared

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@jorgesotomaior8897]

Gracias por la información, fue muy provechosa!

[@AllAmericanFiveRadio]

Thanks very much. You maybe interested in this video also. Pulse Width Modulation Half Bridge MOSFET Driver TL494 2N2222 IRF510 kzbin.info/www/bejne/pIWohZWYo5KXn8k

[@jorgesotomaior8897]

@@AllAmericanFiveRadio Buenisimo, lo voy a ver, gracias y saludos desde Buenos Aires

[@disertronicarf.p.6704]

thanks from venezuela.

[@AllAmericanFiveRadio]

You welcome and thanks

[@andrewferg8737]

Great video! Been looking for ways to incorporate back EMF into a PWM signal. Think this might do the trick.

[@AllAmericanFiveRadio]

Hope it works.

[@andrewferg8737]

@@AllAmericanFiveRadio Curious if you have any tips on transmitting / receiving a PWM signal ? Was planning to have a go a making a radio controller for a motor... Do you simply input the PWM signal where you would normally input an audio modulation signal?

[@AllAmericanFiveRadio]

@@andrewferg8737 Hey Andrew. The guy I build ozone units for is designing a power supply using the TL494. He plans on taking the outputs of the TL494 to drive the Gates of a couple of MOSFETs. Here is my email [e-mail]

[@AllAmericanFiveRadio]

Here's is another Chip to check out FAN7387 DIP-8 FAIRCHILD

[@andrewferg8737]

@@AllAmericanFiveRadio Was looking thru my junk box and found a AP3842CP . I have a go at it once I'm finished with my current project. Another tab on the bucket list!

[@fisrtteknik6496]

Output voltage c1 & c2 must be same or not?

[@AllAmericanFiveRadio]

If you want a different output you could change the value of one of the 1K resistors.

[@fisrtteknik6496]

@@AllAmericanFiveRadio thank for the answer... But when i measure c1=12v c2=5v.... ic is bad or not?

[@AllAmericanFiveRadio]

@@fisrtteknik6496 Keith Hamilton The output should be the same with this circuit. It is possible to change this circuit so that one output has a shorter pulse width.

[@fisrtteknik6496]

Great answer.... thanks bro...

[@Vishalkumar-mu5hy]

How much freq it creates with 10k and 0.01uf.50hz?. If iam not using potentiometer?

[@AllAmericanFiveRadio]

Ask your question again

[@thomc2526]

Thanks for the clear explanation, I appreciate that ^.^

[@AllAmericanFiveRadio]

Thanks, and your welcome.

[@ImTheReal]

You made it looks so simple. Thanks for sharing ^_^

[@AllAmericanFiveRadio]

Thanks

[@thusochiloane8223]

great video thanks for sharing

[@AllAmericanFiveRadio]

Thanks

[@ياسرالعزاوي-ض6ش]

Nice job

[@AllAmericanFiveRadio]

Thank you and your welcome.

[@havatpl]

good afternoon my very interesting friend your schematic I can use the first schematic for a switched source q stopping doing ?? here in brazil did not get one to explain or help could help the brazilian here? good afternoon again !!

[@AllAmericanFiveRadio]

Thanks

[@kolinevans9127]

Thanks for sharing sharing this.

[@AllAmericanFiveRadio]

Thanks and your welcome.

[@carloseduardomoura4992]

muito bom mesmo !

[@AllAmericanFiveRadio]

Thanks!

[@miguelsantana9824]

Nice video.....keep up!

[@AllAmericanFiveRadio]

Thank you, and your welcome.

[@esam461]

Thank you

[@AllAmericanFiveRadio]

Your Welcome