What is negative impedance exactly?

 

According to this Wiki article, it is an "energy injection".. But I'm not sure whether the information is credible.

 

http://en.wikipedia.org/wiki/Negative_resistance#What_a_negative_impedance_is

I do believe you are referring to internal impedance in a power supply. Essentially as you draw more current the voltage drops but if you actually take voltage readings on most power supplies they will drop in a non-linear fashion due to internal resistance. A sudden increase in voltage at a point of greater current draw looks like negative resistance. By internal resistance I mean the rectifying circuitry causes impedance's which also in turn are non-linear due to combination's of fluctuations in frequency and capacitive and inductive reactance. I'm sure there are better explanations but this may point you in the right direction.

 

after wiki

I've never read something in wiki I didn't like but hey the wiki has more power so run with it....................I'll leave this just in in case.

Edited February 2, 200916 yr by buttacup