I have designed 3 power supplies with 3.3 V, 2.5 V, and 1.2 V outputs.
I use BD9870FPS Buck converter to step down 8 V - 24 V to 3.3 V.
Then the 3.3 V is used as inputs for 2 buck converters ENPIRION EN5322QI to step down to 2.5 V and 1.2 V. These 2 power supplies are used for load.
The 3.3 V output is also used for load.
The question is: when I tested three of them, the outputs (voltage) are stable, good. However, the current draw is decreasing while the input voltage to the 3.3 V buck converter is increased. Is this normal?
I read that a buck converter steps down voltage by increasing current. But what I got was another way around.
So, can you help me to explain this?