Opto Couplers

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So, how come they don't make opto isolators in itty bitty SMD parts. This 16 pin 2.54mm spaced part is the biggest thing on the board.

I don't know why I bought the through-hole version rather than the smd version. They're the same size.

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One of the issues is physical separation, inside, for voltage arc-over isolation.

Analog Devices makes some isolators, non-optical, in smaller packages, I think. They use coupled inductors and internally chop the signal. They are pretty good, quite fast, but more expensive.

Jim

 

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The Analog Devices [iCouplers] are capacitively coupled, not inductively [several manufacturers make capacitive digital isolators]. They are pretty large too, for the same reason... you need distance between the sides to prevent arc-over.

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Take a look at Vishay:
http://www.vishay.com/optocouplers/

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shf6916 -- Somebody DOES make one. Wow. Costs twice what the processor costs

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If you know my whole story, you're an accomplice. Keep your mouth shut. 

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Optocouplers in SOIC are not uncommon.

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Yes but considering that the opto is buffering the nasty world from the serene world of the micro shouldn't it be paid more ? ;)

I would rather attempt something great and fail, than attempt nothing and succeed - Fortune Cookie

 

"The critical shortage here is not stuff, but time." - Johan Ekdahl

 

"Step N is required before you can do step N+1!" - ka7ehk

 

"If you want a career with a known path - become an undertaker. Dead people don't sue!" - Kartman

"Why is there a "Highway to Hell" and only a "Stairway to Heaven"? A prediction of the expected traffic load?"  - Lee "theusch"

 

Speak sweetly. It makes your words easier to digest when at a later date you have to eat them ;-)  - Source Unknown

Please Read: Code-of-Conduct

Atmel Studio6.2/AS7, DipTrace, Quartus, MPLAB, RSLogix user

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I DO like its specs.

There is sometimes grounding trouble between the remote control receiver and the sound system, so I'm including an opto coupler so there is no need for a common ground between the two.

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut.