My guess is your circuit is the same thing only done entirely in NAND. This was a recurring theme in my Digital Logic classes. NAND gates were the most mass produced, and hence they were cheaper. This was because any logic circuit can be expressed with NAND gates, there were simple Boolean procedures to convert any logic function into NANDs. Most engineers built logic circuits entirely in NAND, there were few exceptions (sometimes XOR chips made circuits much simpler). The circuit above looks much simpler, but its entirely possible that it costs much more to produce then the one entirely in NAND.
Why the sudden interest in logic circuits? Also, what are you using for learning material? I used to have an awesome digital logic and design textbook, but I have no idea where it went. I used to build awesome little LED ciruits. I used to know Boolean algebra like the back of my hand, Ask Mello.
Clever boy getting me to post on the blog again. I still lerk here, I just lack the creativity to post right now. I'm not going anywhere.
* EDIT * The link to the site that I found the diagram in... http://math.hws.edu/TMCM/java/labs/xLogicCircuitsLab2.html
The sudden interest in digital logic came from a discussion Chris and I had about high level programming vs. low level programming. Our conclusion was that if you wanted to be the hardest core of the 1337 |-|4><0Яz, you would have to build it out of silicone your damn self before you programmed it in machine code. I don't have a text to reference, just what I remember from college and what I can find on the internet, which has fortunately been quite a bit.
ReplyDelete--Andy