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Help repair - identify part (diode) Answered

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Hi,
Need help identifying this part.
It is part of binary input stage, and is not working.
I think it is diode, but not sure. 
If You know what this part is please help.
Thanks.

Tags:400C

12 Replies

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ThirdEarthDesign (author)2017-04-29

The LF markings at the top represents the component manufacturer, LittelFuse.

I believe this is a Transient Voltage Suppression diode. It is lacking a band to denote the cathode because it is bi-directional (this is confirmed by the part number).

The 400 is the rated breakdown voltage, the C indicates it is bi-directional.

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user

Nice one!
Would deserve a "Best Answer" if you ask me...

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user
apofview (author)Downunder35m2017-04-30

Didn't find best answer, there is only feature comment option...

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user

Don't worry, best Answers can only be selected in the 'Answers' section and not the forum. Downunder35m's comment was more of a metaphorical pat on the back.

Hope the answer helps you get it fixed, good luck!

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user

Thanks for identifying manufacturer. Will read datasheet to familiarise with that type of diodes. Big thanks for help.

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Downunder35m (author)2017-04-27

You have any identical parts in the circuit that still work?
If so you could test another one to figure out what it really is.
For SMD components you are often totally lost without a circuit diagram or similar stating the parts.

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apofview (author)Downunder35m2017-04-28

Yes, there are other working parts. Can you suggest me how to determine type? What type of test to do?

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Downunder35m (author)apofview2017-04-28

Just connect it to one of these (the working part) and it will tell you what it is.

http://www.ebay.com.au/itm/LCR-T4-Resistance-Capac...
From there you can try to find a suitable replacement with identical or at least simial characteristics.

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apofview (author)Downunder35m2017-04-30

I always treated this devices as novelties, but maybe it is time to get one and to test how good they are.

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Downunder35m (author)apofview2017-04-30

Me too, until I got one and played around with it.
If you hunt for scrap on old electronics these testers save a lot of time.

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Yonatan24 (author)Downunder35m2017-04-28

It looks to me like it still is on the PCB.

I have no idea, but my only guess is that it says 400C(elsius), so it might have to do with temperature, though probably not because it doesn't look like it could stand that temperature...

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Downunder35m (author)Yonatan242017-04-28

And you would not need 400C° on an input stage for binaries...

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