Another question about core sense amplifiers

Noel Chiappa jnc at
Thu Mar 12 08:45:00 CDT 2015

    > From: Brent Hilpert

    > Similarly, the address-line drivers use a center-tapped primary
    > configuration as a cheap way of providing the bi-directional drive
    > current for the address wires (like push-pull audio).

On re-reading this, to ensure that I had fully extracted the content into my
brain, I realized I didn't fully grok this. Could you expand a tiny bit on
this (and especially the push-pull reference)?

On thinking about it, I guess that what's happening is that there are two
driver transistors, each attached to the center tap and one end, but with the
polarity reversed. A positive pulse through one produces a positive pulse on
the output secondary, whereas a positive pulse through the other produces a
negative pulse on the output secondary. Or am I mis-understanding?

What I don't get is why that's better than simply attaching two opposed
transistors directly to the address lines, as one sees in the output stages
of audio amplifiers, to handle the two halves of a sine wave.


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