SMD Diode identification

Hi guys, I haven't checked in for a while but I know I've been helped before by some really knowledgeable people ... thanks.

The problem at the moment is I'm repairing some cct boards about 10 yrs old (made in Europe) which have smd diodes in the power supply section that I haven't been able to identify ... it's a low voltage input, 27v output switched mode supply.

From the logo they appear to be made by General Semiconductor and I have scoured their site as well as google for hours!!!

The ones I am after are labeled ...
ED78A
RJ78A
ED36A
ED37A
GFR36
GFR77A

The first four appear to be basic rectifiers and the last two ... perhaps suppression diodes maybe.

If someone could help I'd be really appreciative. Thanks.

Regards, Western

http://www.marsport.org.uk/smd/mainframe.htm helps you decode

some samples are here
ED78A EDxx EGF1D Vis I DO214 rectifier ultrafast 200V 1A xx date code
RJ78A RJxx RGF1J Vis I DO214 fast rectifier 600V 1A xx date code

all the best

mvs sarma said:

http://www.marsport.org.uk/smd/mainframe.htm helps you decode

some samples are here
ED78A EDxx EGF1D Vis I DO214 rectifier ultrafast 200V 1A xx date code
RJ78A RJxx RGF1J Vis I DO214 fast rectifier 600V 1A xx date code

all the best

Click to expand...

Hi Sarma,

Thanks for your help. I had been through all the pdf's I have on surface mount components as well as spent hours on Google.

Your lead pointed me in the right direction ... and I eventually came across this page ... http://www.datasheetcatalog.com/generalsemiconductor/31/

which has over 4400 General Semiconductor datasheets.

The problem that had me stuck, was the fact that the same codes are used on different series of components.

I had found the parts you mentioned above, but they had the wrong physical size case!

I went through and opened hundreds of pdf's and eventually found all that I was looking for. Even better was that all are available through element14 here in oz ... so they should be here tomorrow.

I've had this problem many times before and I wish that the datasheets where searchable via Google. The frustrating part is that you need to know the part number of the component before you can open it's datasheet ... and find out what it's identification code is ... talk about the chicken or the egg!

Regards, Western