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7400 competition entry: Analog comparator

Posted on Wednesday, October 12th, 2011 in 7400 contest by DP

Joseph built an analog comparator for the Open 7400 Logic competition.

Using two NAND 3-input gates and a D-type flip-flop, he build a clocked analog comparator. After reviewing the internal composition of a CMOS NAND 3 gate he noticed that two of them connected in the right way make up a comparator. To make his own version he used a D-type flip-flop to save the output value from the gate before it resets on the next cycle. Schematic, as well as some logic gate theory, is available on his site.

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This entry was posted on Wednesday, October 12th, 2011 at 10:00 am and is filed under 7400 contest. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.

One Response to “7400 competition entry: Analog comparator”

  1. rsdio says:

    This one’s a contender. It didn’t look like much in the photo, but this is a very nice abuse of FET logic gates for analog purposes.

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