Diode symbol confusion

[N_Cook]

on one schematic
If a straight bar of cathode and triangle represent a signal diode
Same with a small return towards the triangle from the bar represents a
zener diode
What does the symbol mean with 2 barbs to the bar , one towards the anode
and the other in the other direction.
In the context of the circuit it could mean high speed or shottke , either
or both? just in passing, if anyone happens to know.

 

[JW]

on one schematic
If a straight bar of cathode and triangle represent a signal diode
Same with a small return towards the triangle from the bar represents a
zener diode
What does the symbol mean with 2 barbs to the bar , one towards the anode
and the other in the other direction.
In the context of the circuit it could mean high speed or shottke , either
or both? just in passing, if anyone happens to know.

http://en.wikipedia.org/wiki/Diode
http://en.wikipedia.org/wiki/Zener_diode
http://en.wikipedia.org/wiki/Schottky_diode

 

[William Sommerwerck]

What does the symbol mean with 2 barbs to the bar...?

It's supposed to look something like the letter Z -- hence, a Zener diode.

 

[N_Cook]

It's supposed to look something like the letter Z -- hence, a Zener diode.

That is logical and my experience too but not in this case , hence the
query.
One barb represents zeners in the symbol set used on this schematic, so what
does the 2 barb (normally zener) symbol mean here?

 

[ian field]

That is logical and my experience too but not in this case , hence the
query.
One barb represents zeners in the symbol set used on this schematic, so
what
does the 2 barb (normally zener) symbol mean here?

The various typefaces used by the many people who produce schematics add to
the confusion and some use (often inaccurate) variations of the standard
symbols making matters even worse.

There are of course yet more different types of diode, some of which also
have their own symbol (and variants).

As to answer your original question, it would be hard to improve on the
links JW posted.

 

[Arfa Daily]

It's supposed to look something like the letter Z -- hence, a Zener diode.

I have seen the two barbs being each at an angle to the horizontal bar,
representing a zener, and the two barbs perpendicular to the bar,
representing a Schottky diode. Schottky diodes also seen as the more
elaborate curl at each end of the bar, as shown in the Wiki reference.

Arfa

 

[shrtrnd]

Schottkey diode symbol should have extra turn at the end of each of the barbs, pointing back into the device. I see a lot of unusual symbols out of foreign countries though. If you're sure you've got barbs at ends of cathode symbol (one toward anode, other toward cathode), and you're sure it's not a zener, ...Schottkey is likely.
Single barb toward anode is a 'breakdown' diode. Double barb toward anode is a 'tunnel' diode.

 

[Meat Plow]

I have seen the two barbs being each at an angle to the horizontal bar,
representing a zener, and the two barbs perpendicular to the bar,
representing a Schottky diode. Schottky diodes also seen as the more
elaborate curl at each end of the bar, as shown in the Wiki reference.

Arfa

Shotts look more like an S for an obvious reason