Re: what is a "flatpack" transformer?

apa <tacoma57@xxxxxxxxxxx> wrote:
Scott D. has mentioned these on a number of occasions. What exactly
makes a transformer a "flatpack" and what's their advantage?

It's a particular variant of the EI core, designed for low profile.

The main advantage of them is that they are flattened, so you can stick
them into a 1U cabinet or into the corner of a mike body.

Here's an example: http://www.belfuse.com/Data/DBObject/2-48.pdf

Since most of them are built with separate bobbins for each winding, they
usually have very good electrical isolation between windings. That could
mean low induced noise from the power line.

The bad news is that they are usually less efficient than a standard
EI-core type. The higher losses mean the configuration is no good for
input transformers and other applications where efficiency is important.
They mostly get used for power transformers and you will very occasionally
see output transformers built that way.,
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
.

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