Hello Forum!

I ask for your help please to identify this SMD parts with the ledgend "GGG 72A" I think that there are a Diodes, but I do not know wich are. The circuit is a Poe injector.

Thanks in advance for your help!...

Best regards!...

 

they are both diodes

 

they are both diodes

Yeah...but what kind of diode is it. That would be a lot more helpful

 

I recognize the white components as Comgap gas discharge tube (GDT) surge
arrester devices. Has used them my self in medical devices. I also recognized the symbyl on the SMD as a symbol used on components from Vishay. That lead to that the components probably was some kind of transient voltage suppressors. And indeed that was correct The GGG is the type marking. And since it has no markings it is bi-directional
http://www.vishay.com/docs/88394/88394.pdf
http://shpat.com/docs/elfa/06050009.pdf

 

Looks like they go from the two power rails to the ground plane, it's really unlikely they are rectifier diodes.

My guess is that (like the two gas arrestors) they are some type of transient protection, like transorbs or even MOVs.

 

Measure them with a DMM continuity tester. Schottky give some 110 to 200mV. Regular diodes- 500mV.

Coils give nearly zero Ohms.

 

And since it has no markings it is bi-directional

bi-directional Transorbs have a CA suffix.

 

bi-directional Transorbs have a CA suffix.

Oh thank you pointing that out. Important then ordering. But I do not the CA suffix is icluded on the SMD package. To me it looks like they use band/no band