Octal D Type Flip Flop DIP
I found this pack of DIP (dual inline package) chips at the fleamarket in Brimfield this weekend. They caught my eye just because the packaging looks so old. DIPs were first commercially manufactured in the 1960s but this pack was made on June 30, 1994, relatively close to the day I was born. I have never seen a pack of integrated circuits with "Flip Flop" written out on the package. Flip flop refers to a circuit with two states, the states can be changed by applying a signal to one of the control inputs. This change in the input changes the output. Flip flop logic is a fundamental part of most modern micro circuits which is why I thought it was interesting to see it here. Most ICs now have simple logic built right into them because they carry out very complicated tasks. The logic here is very important in sequential data storage because flip flops are good for storing states.
Used to see these 74xx-series discrete logic chips on the shelves a lot in the late 80's / early 90's when I first got interested in robotics. That's all we had, really. Well, maybe Motorola 68HC11 microcontroller but I couldn't afford one. And writing up a CPU was non-trivial and required lots of TTL. It was a few more years before PIC and AVR had eeprom-based microcontrollers that hobby roboticists started to use. Until then you could browse thru flip-flops, NANDs, NORs, ANDs, ORs, XORs, counters, inverters, muxes/demuxes, and so on to build your project. Our college classes were CPU- and TTL-based.
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