RE: Why are some optocouplers white and some black?

[email protected] Thu, 01 Jun 2006 14:40:26 -0400

This is a multi-part message in MIME format.

I have one bit of information to add to the mix.


A co-worker, who is more an old-timer than I, recalls that when the
translucency problem was solved it was during VDE approvals at some
company whose name he does not recall.  The story goes that, as proof
that the problem was fixed they started using white bodies for the ICs
instead of black.  If true, it sounds a little like an advertising
trick.

If there are any opto-folks on this discussion group I would like to
hear your perspective.



Doug Powell, Staff Engineer
Corporate Compliance Dept.
Advanced Energy Industries Inc.
 

From: Powell, Doug [mailto:[email protected]] 
Sent: Wednesday, May 31, 2006 11:03 AM
To: [email protected]
Subject: Why are some optocouplers white and some black?


This is obviously a trivia question but I think is related to product
safety.

My recollection is that early on, some manufacturers designated white
body optocouplers as the only type that had certain attributes, like
agency approvals.

It would seem that a white body would be more translucent and you risk
falsely triggering the transistor.
        

-Doug

Doug Powell
Advanced Energy Industries Inc.
Fort Collins, Colorado USA

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Title: RE: Why are some optocouplers white and some black?

I have one bit of information to add to the mix.

A co-worker, who is more an old-timer than I, recalls that when the
translucency problem was solved it was during VDE approvals at some
company whose name he does not recall. The story goes that, as proof
that the problem was fixed they started using white bodies for the ICs
instead of black. If true, it sounds a little like an advertising
trick.

If there are any opto-folks on this discussion group I would like to
hear your perspective.

Doug Powell, Staff Engineer
Corporate Compliance Dept.
Advanced Energy Industries Inc.

-----Original Message-----
From: Powell, Doug [mailto:[email protected]]
Sent: Wednesday, May 31, 2006 11:03 AM
To: [email protected]
Subject: Why are some optocouplers white and some black?

This is obviously a trivia question but I think is related to product
safety.

My recollection is that early on, some manufacturers designated white
body optocouplers as the only type that had certain attributes, like
agency approvals.

It would seem that a white body would be more translucent and you risk
falsely triggering the transistor.

-Doug

Doug Powell
Advanced Energy Industries Inc.
Fort Collins, Colorado USA

-
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Scott Douglas [email protected]
Mike Cantwell [email protected]

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