Hello,
I have noticed some strange current fluctuations through some (not all) Vishay diodes I am trying to understand better. Basically I am seeing up to a .34 ohm fluctuation through a 1N5404 diode operating at 1A/28VDC which results in a current change of ~.012A of the circuit. In most cases for the first handful of cycles, the fluctuations are not noticeable, but they begin to appear out of the blue and do not go away. Any information that can help explain this phenomenon would be greatly appreciated.
Thanks,
Phillip

 

Without a schematic of the circuit, any answers are just WAGs.

 

I asked the wife and the girlfriend but they don't know either.

 

Real simplified, Vs = 33v, RL = 28V and there is .012A current fluctuations which is determined by measuring Vo.

 

Take a look at the diode equation:

ID is an exponential function, highly dependent on VD and temperature. A slight change in either can cause a large change in ID.

 

RL = 28V?
Do you mean RL = 28Ω?
Is Vs 33VAC or 33VDC?

 

If you are seeing such fluctuations with a steady dc source than something is wrong with the diode.
What is their frequency?
Have you looked at the source to see if it is stable?