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Electronics => Projects, Designs, and Technical Stuff => Topic started by: viktor18 on June 09, 2017, 09:36:30 pm

Title: Identifying this diode
Post by: viktor18 on June 09, 2017, 09:36:30 pm

I need some help on identifying this diode, unfortunately it has been shorted and need a replacement
(http://i66.tinypic.com/vde7fa.jpg)

The marking on it says: MK 7CE

Title: Re: Identifying this diode
Post by: DmitryL on June 09, 2017, 09:45:16 pm

Quote from: viktor18 on June 09, 2017, 09:36:30 pm

I need some help on identifying this diode, unfortunately it has been shorted and need a replacement
The marking on it says: MK 7CE

Look to me as SMBG30A 33v TVS

Title: Re: Identifying this diode
Post by: viktor18 on June 09, 2017, 09:58:41 pm

How would I be able to confirm?

Title: Re: Identifying this diode
Post by: Nusa on June 09, 2017, 10:57:21 pm

To confirm, since he gave you a part number, is to find the datasheet for that part number.

To find it in the first place:
The device code is "MK", the 7C is a date code (year ending in 7, december), E not sure...maybe production facility.
Google "diode MK mark", and that'll lead you to a suppliers datasheet that includes it, such as: https://www.vishay.com/docs/88456/smbg.pdf (https://www.vishay.com/docs/88456/smbg.pdf)

Title: Re: Identifying this diode
Post by: David Hess on June 09, 2017, 11:23:31 pm

Are you sure it is not in parallel with L902?  If it is in parallel with an inductor, then it will appear to be shorted when measured in the circuit.

Title: Re: Identifying this diode
Post by: viktor18 on June 10, 2017, 10:47:29 am

Thanks for all your replies! I'm positive that the diode is shorted.

I managed to find a replacement diode from the original part ( at least I hope so)
(http://i64.tinypic.com/w8mczl.jpg)
(http://i65.tinypic.com/14bmjh4.jpg)

with
(http://i67.tinypic.com/1zd9n5c.jpg)
(http://i66.tinypic.com/2mfmaf5.jpg)

For me it looks like a suitable replacement, but original part says Stand-off voltage 30v and the replacement says Reverse stand off voltage 30v.. What's up with that?

Title: Re: Identifying this diode
Post by: Nusa on June 10, 2017, 11:23:26 am

Quote from: viktor18 on June 10, 2017, 10:47:29 am

Thanks for all your replies! I'm positive that the diode is shorted.

I managed to find a replacement diode from the original part ( at least I hope so)
(http://i64.tinypic.com/w8mczl.jpg)
(http://i65.tinypic.com/14bmjh4.jpg)

with
(http://i67.tinypic.com/1zd9n5c.jpg)
(http://i66.tinypic.com/2mfmaf5.jpg)

For me it looks like a suitable replacement, but original part says Stand-off voltage 30v and the replacement says Reverse stand off voltage 30v.. What's up with that?

Same thing, just labeling variation. Below the 30V standoff voltage, reverse flow is blocked, letting no more than 1 microamp of leakage through.

Title: Re: Identifying this diode
Post by: viktor18 on June 10, 2017, 11:25:54 am

Quote from: Nusa on June 10, 2017, 11:23:26 am

Quote from: viktor18 on June 10, 2017, 10:47:29 am

Thanks for all your replies! I'm positive that the diode is shorted.

I managed to find a replacement diode from the original part ( at least I hope so)
(http://i64.tinypic.com/w8mczl.jpg)
(http://i65.tinypic.com/14bmjh4.jpg)

with
(http://i67.tinypic.com/1zd9n5c.jpg)
(http://i66.tinypic.com/2mfmaf5.jpg)

For me it looks like a suitable replacement, but original part says Stand-off voltage 30v and the replacement says Reverse stand off voltage 30v.. What's up with that?

Same thing, just labeling variation. Below the 30V standoff voltage, reverse flow is blocked, letting no more than 1 microamp of leakage through.

Alright thanks! I'll give the replacement a try.