Using Chips

Op-Amps are the first components we've used that are integrated circuits, which are also called IC's or chips. IC's are easy to use, but we need to know a few things about them.

We'll be using chips that come in a DIP package, which has pins that plug right into our breadboards. Be careful not to order IC's that aren't in the DIP style, as these won't fit right.

Static electricty can fry certain chips, especially those using what's called CMOS technology. Before picking up a chip, ground yourself by touching something grounded, like a radiator. Then, try to handle the chip without touching the metal pins.

To insert a chip, put the pins across the trough in your breaboard, and gently push down until you feel it lock in. Be careful not to bend the pins.

Each pin has a number. Pin 1 is identified by a dot, and is also to the left (looking down) of the notch on the casing. From there, the pin numbers proceed counter-clockwise. Use the datasheet of the chip to tell you what pin does what. For example, here's one from the 324A Op-Amp:

Remember that every chip needs power. Connect V+ (also called Vcc) to your top power bus using a red wire. Use a black wire to connect V- to GND (0V), or a blue wire to connect V- to a voltage level below GND. Using the correct color wires will help you keep track of what's going on in your circuit.

If your circuit is powered by a source with line noise, like a DC power supply that converts from AC, it's a good idea to put a small ceramic cap between the V+ and V-/GND pins of an IC. This cap will filter out the noise and make your chip work more reliably.


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