Knowing your chips
The type of chips or integrated circuits (ICs) used in a MTX are in packages known as DIL. This means Dual In Line. DIL chips come in many different sizes depending on how many pins are present. They come in two widths - 0.3 inch and 0.6 inch. The spacing between the centre line of each adjacent pin is 0.1 inch.
DIL chips are available in two materials - plastic and ceramic. Plastic is the most common as it is the least expensive. Normal windowed EPROM chips are always supplied with a ceramic package.
The way the pins are numbered and the mark that identifies which pin is pin one often confuses people.
For some examples look closely at this picture:-
- DIL chip pin numbering.JPG (102.31 KiB) Viewed 6559 times
Some chips have a dimple or small circle moulded or screen printed next to pin one. The top two chips in the picture use this method. Some use more than one method.
Mark
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