Need help identifying SMD

Need help learning to read SMD marks so I can replace some of them

I know it’s a LittleFuse brand at least

Hello, Clmedina. Welcome to TechForum!

Do you have any additional information on this device? Suspected function? Apologies, there’s no universal decoder for SMT device top markings. Every manufacturer has different marks, and in most cases every product series or individual part number has its own markings. Your parts look like SMT TVS diodes, a few examples here: , but the ‘MP’ and the ‘117YR’ are coming up blank. I strongly suspect 117YR is a date/lot code, but haven’t had luck with the ‘MP’. Any additional information I can use to run another search?

Hi @clmedina121 ,
There is a small chance, that this device is SMBJ36A.

Cheers, heke
P.S. For a few decades I’ve assumed that the company’s name is “Littlefuse”, but just recently was shocked to discover that the name is actually “Littelfuse”. I hope I am (not) the only one…


Yes, looks like part SMBJ36A matches the marking scheme. It also took me awhile to realize the spelling on Littelfuse.

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Good job, heke! That’s the right part!

Regarding Littelfuse, I noticed that spelling quite some time back, but I still have to remind myself of how to spell it by saying to myself → “li-Tell fuse” rather than “little fuse”.