Jim Thompson wrote:


An XOR is a convenient structure to allow a control signal to invert or
non-invert another signal.

Trouble is (as classically done) inverting has 3 stage delays, while
non-inverting has only 2.

Anyone know of a configuration that has symmetric delays?

I'm concluding the best I can do is fudge some sizing to somewhat
equalize delay paths.

How about something like this:

http://www.abvolt.com/misc/xor.jpg


Vladimir Vassilevsky
DSP and Mixed Signal Design Consultant
http://www.abvolt.com