Part Number: TIDA-010080
Other Parts Discussed in Thread: UCC28180, UCC256402
Hello,
I made a board based on the schematic of the TIDA-010080 evaluation board, using the UCC28180 (for the boost), the UCC256402 (for LLC) and the 750344508 transformer from Wurth.
As I needed 250W power and 80V output, with the advice of the transformer manufacturer (Wurth), I connected the secondary windings in series.
With the help of the calculator supplied by Texas Instruments, I calculated the polarization components for this power with a working frequency of 100KHz.
In operation, I manage to get the output voltage to 80V at no load, but I can't supply the current as soon as I place a load at the output.
Switch frequency measurements give me a frequency of around 300Khz at no load and 400khz when the board is under load (Rl=1Kohm).
The component values are: Lr=22uH and Cr=66nF. I've also tried different values of inductance (33uH, 47uH and 100uH) and capacitance (from 10n to 99nF), but nothing conclusive.
I need your help to understand why I don't have the calculated frequency. If you need other elements, don't hesitate to ask me.
Thank you
