Recalling this question: Choosing series resistors for zener diodes
I thought to open a new question related to this, because it is centered to a specific part of the old question.
It is said that, when a Zener of a given voltage is used with a lower current than the tested one, it provides a smaller zener value. I tried with the BZX84C3V3 and applying 5V with a 560Ω: I have a bit more of 3.3V, which is reduced when using 2.2kΩ. Does the zener cut the voltage better (or even to a low voltages than 3V3) when derated in current?
This is coherent with the datasheet, but I don't get the logic: doesn't the Zener shall be less opened to GND with lower current? And being less open, more zener resistance shall be present and according to the voltage divider, I shall see an higher voltage. Instead, it is happening the opposite.