half bridge using uc3825

[emiljose88]

Hi Guys

I wish to done a half bridge using UC3825( up to 400W). Can you suggest any guidelines to my project?

 

[goldsmith]

Dear emiljose
Hi
It is pretty simple . but i think you forgot to mention your problem . If you describe your problem , i can help you as well .
Best Wishes
Goldsmith

 

[emiljose88]

thanks
can you give any ckt diagrams using half bridge, UC3825

 

[goldsmith]

Did you see it's dataseet exactly ? It has two out puts , first is PWM and the other is PWM' . so you can drive a half bridge simply .
But i think you are not familiar with Half bridge , right ? we have two model for half bridge ( two usual mode ) . first one with simultaneous supply and the other with single supply and two capacitors .
Good luck
Goldsmith

 

[emiljose88]

thanks
first time i'm going to design a half bridge

Vin-150V to 265VAC
output- 15V 20A smps


can you help me seriously, with schematics (UC3825)

 

[goldsmith]

Sure , no problem . at first you should the frequency of PWM .
If you increase the PWM frequency we will have an advantage and a disadvantage : advantage : magnetic elements will have low size . and disadvantages : 1- at high frequencies skin effect will suffer you . 2- the dissipation will increase .
Hence i think 100 KHZ will be good choice for you . so you should select two mosfet that can work at this range of frequency , as well .
Best Wishes
Goldsmith

 

[emiljose88]

thanks
can you send any ckt diagram.

 

[goldsmith]

Of course , some hours later i'll send it .

 

[emiljose88]

hi guys
can you send any schematics.

 

[goldsmith]

Oh sorry , i forgot it completely
See below , please :

And for feed back you'll need a tl431 and an opto coupler .or a simple zener diode and an opto coupler .
i think you're able to work with that driver . did you read it's datasheet ?
Best Wishes
Goldsmith