Hello
I am designing a 1200W DC / DC power supply. I'm using a fullbridge and the integrated ucc28950, and I've followed the application notes to design the circuit. I have set the output to 65V and an input of 18 to 40V. The ratio of the transformer is 1: 4. When the input is the minimum, the circuit uses the maximum duty cycle, and the circuit works perfectly, but when the input voltage decreases, the duty cycle does not decrease but maintains the duty cycle maximum, and the controller turns off a period of weather. The next image is the voltage in the transformer.
The output voltage is still maintained at 65V regardless of voltage and load (within design parameters). The current is less than 2V.
Is this behavior normal?
