4 ms·
For counting chips, remember that each 74xx chip typically has multiple gates. For example, one of them has four AND gates, and another has six inverters.
by jewillco 3y ago
For counting chips, remember that each 74xx chip typically has multiple gates. For example, one of them has four AND gates, and another has six inverters.
- retrac 3y agoSometimes, many gates! The 74xx series shows the progress of semiconductor technology over time. Later 74xx series chips are MSI. Oh, that term is quite antiquated now isn't it? Medium-scale integration. (Just about everything is far beyond VLSI these days. Very large scale integration.) The 7400, the first device in the series, was just four NAND gates in one IC. NAND is the easiest function to implement in TTL (and most other logic families). The somewhat later 7476 is a dual JK flip-flop. It takes eight NAND gates to make a JK flip-flop, so a 7476 is about four times denser than the 7400. And devices like the even later 74161 4-bit synchronous binary counter have many dozens of gates [1], being roughly four times as much integration again over the 7476. The 7400, 7476, and 74161 were at the cutting edge of integration in 1963, 1966, 1969, respectively. [1] https://makeyourownchip.tripod.com/74161.GIF https://makeyourownchip.tripod.com/74161.GIF