Problems with a source of 12V x 4A using TOP256EN
I generated the source for PI Expert Program 8, with input from 85 to 265VAC 60Hz, and output of 12V x 4A using TOP256EN.
I'm calling it at 220V, the voltage reaches the max and 9V TOP256EN (U1) is damaged. I had to make some modifications for not finding the exact components.
R1 24k 2w, I'm using 22k 2w
C3 x 3.3 nF 1KV, I'm using 2.2 x nF 1KV
D1 FR106, I'm using UF4007
D2 MUR110, I'm using MUR120
But the rest of the circuit'm riding as recommended.
In transformer design, asked 188uH the primary, measured with the multimeter and is giving about 210uH.
The problem could be the transformer?
Comments
I put the 22u capacitor C3 in Tl431 and changed to 4.7 nF, yet the source does not work properly, and continues to damage the ic Top256EN, the project is actually correct or is missing something?
I do not know what else to do to solve this problem. I swapped the trafo three times ic and burning the remains.
The attached layout shows long traces between power switching components, C2/T/U1 and T1/D3/C9,C10.
These components need to be close to minimize the leakage inductance.
High leakage inductance can create high voltage spike on TOPHX, and it can cause a failure at high input voltage.
Please refer to recommended layout guide in TOPHX datasheet.
but the project's source is correct?
I need to add or remove any components or change any value.
Once I turn on the power ic U1 is damaged instantly.
Had something else should I check?
Instead of using FR106'm UF4007, R1 24K and 22K'm using C3 3.3 nF 4.7 nF'm using. This can cause problems?
You need check the fallowing wave forms
1) What is the drain voltage at maximum input(o/p Should be at maximum load).
2)What is the maximum Vcc (bias voltage).
The solution is
You need to add a TVS Clamper in the snubber circuit .and also add a zener diode in reverse bias to 256(but it is the optional for you)
but main thing is you nee to place TVS clamper it should capable of clamping at least 200V.
I don't think so. Try to shunt cathode-anode TL431 by capacitor app. 22 microfarade - it's give you soft start. I think you need it because you have large capacitance on output - it's look like short-circuit for starting. And it seems to me that value of R10,R11 not correct. You must have 2.5V on control pin TL431, but with those nominals you have just a little above 3V. May be something else, but too late for me - I'll go sleep :)
Oh ye! C3 must be 3.3nF!