Unknown component

Hello
I need some help to identifying for the following 4 SMD components, I suspect they are TVS bidirectional diodes but I am not sure about this.The manufacturer was General Semicondoctor and is now Vishay. The the inscription on the components are: CK67A - CK5CA - CK64A and BBMGP37
Dimensions are 5.3 x 3.4 mm I think smd package type 1812?
I have searched the entire internet but cannot find any results.
Various search engines also give no results. Hopefully someone of you knows these codes and which component it concerns. I know that the manufacturer has been taken over by Vishay, but on there site I don’t come across these codes also .

Welcome to the Technical Forum. I am in agreement with you on this. I am not finding anything. The first three numbers concern me as they are so similar. I have tried all of them. They could be proprietary. Not sure. The last one I did not find anything either. Though I am not the only one that might answer on this. So hopefully someone is able to find something.

I’m not having any luck yet either. Perhaps some images might help?

Hi thanks for the quick responses to my problem, here are a few photos of the components



Hello - according to the datasheet (see page 2) these TVS diodes
SMAJ30A are marked with CK.

Need to check your dimensions carefully. The part listed above is an SMA package and would have a polarity line on one side. The SMA package has following specified dimensions:

I suspect you have an SMB package, which has the following dimensional specs:

And it does not look like you have a line on one side, which implies that it’s bi-directional. If so, it’s most likely the SMBJ30CA. The datasheet shows the following package marking:


The other letter and number markings are likely lot codes. The logo is definitely General Semi, so I’m pretty sure we have it here…

Hi David,
Thanks for your update I also think you are right about the fact that they are bidirectional diode components, because there is no Cathode mark on either side, I’am sure they are diodes because the components are labeled as D8 and D9 on the PCB board.
I measured them again out of the board now and came up with the following sizes:
length 4.3 mm width 3.5 mm height 2.3 mm
I think this corresponds to the dimensions for an SMB
So I think thanks to you and the other help here now I have found the right replacement for this component. Thank you all for your help guys, we can close this item now

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