Hello Folks,
It's the old zener issue but I started a new thread because it's not about sources anymore. Rather, I found that quite a few data sheets specify a really high impedance at the rated zener current. For example, these low current zeners are spec'd at 250uA yet the data sheet says that their impedance at that current is over 1000ohms:
That would make the voltage slide all over the place. The only situation where I have encoutered such high impedances is when operating zeners in the knee. My question is: Could this mean that they aren't really low current zeners but just regular ones that have been labeled with a lower voltage and really operate in the knee when run at their rated Izt?