I just saw a post in Homework wherein the TS is allowing 4 ua for an 18 volt zener diode. 30 volts, 3 meg, 18Vz, ground. Has the state of the art progressed that far? Is this a feature of the simulator? What's up with this?

http://forum.allaboutcircuits.com/t...yback-converter-when-load-is-attached.109644/

 

In theory it isn't too big a leap -- you just have to be able to make the junctions small enough (of course nothing is really as simple as that).

A quick search on low current zener diodes reveals that ON semiconductor has a line of low current zeners and their 18V zener is spec'ed at 50uA of reverse current. A current of 4uA is only an order of magnitude from that and it wouldn't be too surprising that a line of diodes beats the first hit I found by that much.

Still, the person in that thread should made aware that they need to verify that they aren't starving their zener.

 

Love the headline No12.

 

Darm ! I mistook the headline.!!!
Good one #12

 

I just saw a post in Homework wherein the TS is allowing 4 ua for an 18 volt zener diode. 30 volts, 3 meg, 18Vz, ground. Has the state of the art progressed that far? Is this a feature of the simulator? What's up with this?

http://forum.allaboutcircuits.com/t...yback-converter-when-load-is-attached.109644/

I noticed on the schematic that "Vin 30-800VDC". This could get interesting...

 

To recycle a post from another recent thread...

You and your sensationalist headlines! ...

From this recent thread...
#2

 

I dunno Gopher. I made up a sensational headline about a real concern. Martinez comes up with things I simply don't believe.

@GopherT After letting this stew for an hour, I remember that sometimes I try on the behavior of other people to see how it feels...especially if I feel a deep objection to it. After I try it on and see how it fits, I usually find out why I objected in the first place. Then I decide whether it was merely a prejudice from long ago. It's a form of reality testing for emotions. The old, "Walk a mile in his shoes" theory.

 

I dunno Gopher. I made up a sensational headline about a real concern. Martinez comes up with things I simply don't believe.

@GopherT After letting this stew for an hour, I remember that sometimes I try on the behavior of other people to see how it feels...especially if I feel a deep objection to it. After I try it on and see how it fits, I usually find out why I objected in the first place. Then I decide whether it was merely a prejudice from long ago. It's a form of reality testing for emotions. The old, "Walk a mile in his shoes" theory.

The title of your post made me laugh and then open it to see what the hell you were talking about. A few minutes later I scrolled to the top of Martinez's thread to figure out how that mess got started and I see your headline criticism - I just had to cross-post it because it made me laugh. Not laughing because of your inconsistency - that's natural for open and creative people - I laughed because it was a chance in a million to have two such posts on back-to-back threads that I happened to read.