Lab1 wiki (en)

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Chips and Breadboard dil16.png

At the labs, we use digital circuits from the so-called 74-series of capsules of the DIL type (Dual In Line) for hole PCB assembly. See the picture. This is today considered to be pure spare parts, and development has changed to completely different package types for surface mounting.

These old circuits, are however unbeatable for experiments with simple connections on the breadboard. Breadboard are now also used with very complex circuits - then mounted on Breakout Board (a breakout board has the same pin spacing DIL) circuits. Working with circuits on the breadboard is therefore the natural working method for project work and theses for school and hobby activities.fritzing.gif

Fritzing Is the name of a software for documenting breadboard connections, and generate circuit diagrams, and possibly manufacture printed circuit boards. (This program will be used in the course IE1206 but is not needed for this course). Anyone interested can download it now.

Data sheets for laboration circuits The digital components have capsules with 14 or 16 pins. For orienting the capsules they have an outlet on the short side, and there can also be a "dot" to mark the pin number 1. Two of the pins should be connected to the supply voltage and ground and the other pins are used as logic inputs and outputs, sometimes a pin can lack connection to the inside of the chip, it is then called NC (no Connection). The pin function is stated in the data sheets, and to some extent also in the symbols in the figures.¶

Some warnings. Two outputs may not be connected with each other. It will be a so-called short-circuit and the output value becomes uncertain 1/0 (?). Unconnected inputs picks up electrical interference and must therefore also be considered unsafe 1/0 (?). They should therefore always be connected to an appropriate fixed level 1/0 depending on the function.¶