Hi,
Here's a schematic of complete power supply using TL494. I had tried this and it works perfectly. I'm using EPCOS E32-16-9 N87 grade core and adjust the frequency to 80Khz.The specs from EPCOS says the core can handle 500W Max. at 100Khz.
Check here:
http://www.audiohobbyist.com/caraudio.htm
Hope this help.........
Here's a schematic of complete power supply using TL494. I had tried this and it works perfectly. I'm using EPCOS E32-16-9 N87 grade core and adjust the frequency to 80Khz.The specs from EPCOS says the core can handle 500W Max. at 100Khz.
Check here:
http://www.audiohobbyist.com/caraudio.htm
Hope this help.........
Good PWM Chip(s)
Hey Guys,
Check this chip out-
ON Semi's MC33025. Originally based on the SG3525, it has a higher bandwidth error amp, oscillator up to 2MHz, totem-pole outputs good to +/- 2A (for driving really BIG MOSFETs) 
, and can operate either voltage- or current-mode , like the UC1846. Go to ONSEMI.com and look up MC33025 in the search line. This chip is identical to Untirode's (Now TI's) UC3825. 
BTW, the MC- prefix comes from the fact that it was around before Motorola spun off their semiconductor products sector.
Best of all, you can get FREE samples from ON's website. Try to limit to only a few at a time.
I have used this chip, and for hard-switching PWM control applications, this is the best (and easiest ) chip I have used.
For those who may have used this chip, Please post your experiences. Thanks!
'73, de N8XO
Hey Guys,
Check this chip out-
ON Semi's MC33025. Originally based on the SG3525, it has a higher bandwidth error amp, oscillator up to 2MHz, totem-pole outputs good to +/- 2A (for driving really BIG MOSFETs) , and can operate either voltage- or current-mode , like the UC1846. Go to ONSEMI.com and look up MC33025 in the search line. This chip is identical to Untirode's (Now TI's) UC3825. BTW, the MC- prefix comes from the fact that it was around before Motorola spun off their semiconductor products sector.
Best of all, you can get FREE
samples from ON's website. Try to limit to only a few at a time.I have used this chip, and for hard-switching PWM control applications, this is the best (and easiest ) chip I have used.
For those who may have used this chip, Please post your experiences. Thanks!
'73, de N8XO
Hi RX5,
No, that is E type, which is 2 pcs of E shape core with a plastic bobbin. You can download the specs from Epcos web site,
here's the link:
http://www.eastern-components.com/epcos-lframe-elib.htm
and download the design tools and you can design your own transformer for PWM type power supply.
I had read a lots of articles, toroid is not design for power trans, it can be used as power trans but I prefer proper core so that I can design virtually any wattage I want. I have E55 type core which can produce nearly 2KW while working at higher frequency, but car battery is a main problem here, current will be too high, around 185Amp while blast to full power........
enjoy!
No, that is E type, which is 2 pcs of E shape core with a plastic bobbin. You can download the specs from Epcos web site,
here's the link:
http://www.eastern-components.com/epcos-lframe-elib.htm
and download the design tools and you can design your own transformer for PWM type power supply.
I had read a lots of articles, toroid is not design for power trans, it can be used as power trans but I prefer proper core so that I can design virtually any wattage I want. I have E55 type core which can produce nearly 2KW while working at higher frequency, but car battery is a main problem here, current will be too high, around 185Amp while blast to full power........
enjoy!
hello all here is MY update..... TL494 CAN be used in SMPS/car amp.... just did/actually tested these a few days ago... now its driving my 100W RMS amp/subwoofer assy..
SG3525 chips require no buffer?? (correct me if im wrong) when driving N-ch mosfets.....like SG3525 ->> N- mosfets
while....
TL494 needs one.... a basic push-pull (npn-pnp) buffer is all that is needed to drive the N-Ch mosfets.... and everything worked out beautifully... TL494 ->> npn/pnp buffer ->> N- mosfet
Ive been playing around with TL494 before.. and it always HEATED up my mosfets... not knowing I was driving them in the linear region....
what the circuit REALLY needed was a buffer betweeen the chip and the Mosfets.... the TL494 is running in push-pull mode @100KHz... works GREAT!! ive even added up a softstart ...
I can post diagram if your interested... no PMs pls...
OK! Beautiful work guys!!!
I want to construct it
The only problem is that I have one ETD44 and two ETD49 transformer cores....
Could please somebody answer me.... how much power I can get from these cores. In my country I can't by anything else.
I need 400 to 500W of power. I have searched sites and there is nothing about real power... hundreds of hard formulas.
From this thread I now almost everything about schematics!!! Four pairs of IRFZ44 and it will be 500W..... just transformer
The frequency I will set buy your recommendations!
Please help!!!
Thanks!
I have created amp already... just SMPS!
I want to construct it
The only problem is that I have one ETD44 and two ETD49 transformer cores....
Could please somebody answer me.... how much power I can get from these cores. In my country I can't by anything else.
I need 400 to 500W of power. I have searched sites and there is nothing about real power... hundreds of hard formulas.
From this thread I now almost everything about schematics!!! Four pairs of IRFZ44 and it will be 500W..... just transformer
The frequency I will set buy your recommendations!
Please help!!!
Thanks!
I have created amp already... just SMPS!
Attachments
Toroid Data for Car SMPS
Hi Himanshuruval. Personally I would recommend you use the ETD39 with Ferroxcube 3C90 core halves or similar material. This is suitable for building car amplifiers which deliver around 350W RMS total continuous power. If you need more power than this you can try the next bigger core which is the ETD44 core with the suitable 3c90 core halves. The power you can get out of any particular core is dependent on frequency. Running the cores at around 100KHz is not a bad start.
About 4 turns on the primary will be sufficient for most cases. The number of secondary turns will of course depend on the output voltage(s) which you require.
If you must use a toroid then you can use something like the Ferroxcube TX42/26/13-3C90 or something similar.
Hi Himanshuruval. Personally I would recommend you use the ETD39 with Ferroxcube 3C90 core halves or similar material. This is suitable for building car amplifiers which deliver around 350W RMS total continuous power. If you need more power than this you can try the next bigger core which is the ETD44 core with the suitable 3c90 core halves. The power you can get out of any particular core is dependent on frequency. Running the cores at around 100KHz is not a bad start.
About 4 turns on the primary will be sufficient for most cases. The number of secondary turns will of course depend on the output voltage(s) which you require.
If you must use a toroid then you can use something like the Ferroxcube TX42/26/13-3C90 or something similar.
Suitable Transformer Cores
A couple more choices to consider if you want to use a toroid are either the Amidon FT-140-77, or FT-240-77. The '140 has about 350W throughput capacity @ 100kHz, and the '240 can throughput about 1.7kW @ same freq. Both are made of #77 Ferrite material, which is great for SMPSs. The FT-140-77 is 1.40" O.D. and the FT-240-77 is 2.40" O.D. Primary turns for either core should be about the same: 4 + 4, but you will want to verify this through a good design regimen.
Hope this helps,
Steve
A couple more choices to consider if you want to use a toroid are either the Amidon FT-140-77, or FT-240-77. The '140 has about 350W throughput capacity @ 100kHz, and the '240 can throughput about 1.7kW @ same freq. Both are made of #77 Ferrite material, which is great for SMPSs. The FT-140-77 is 1.40" O.D. and the FT-240-77 is 2.40" O.D. Primary turns for either core should be about the same: 4 + 4, but you will want to verify this through a good design regimen.
Hope this helps,
Steve
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