Logic gate IC's:

Although it is possible to make your own logic gates using basic components such as transistors and resistors it is usually easier and cheaper to uses dedicated IC's (integrated circuit). A integrated circuit is a semiconductor that is designed to perform a very specific function, for example a 555 timer IC is designed to generate a very stable oscillating signal with the help of some basic passive components like resistors and capacitors.

During this workshop we will work with logic gate ic's. The logic gates we will use all belong to the same family: the 4000 series. All logic gates that belong to this family work together (they operate at the same voltage, and the in and outputs can be connected together without the need of other components*). The 4000 series logic gates can be split into 3 groups:

• 4 channel 2 input gates
• 3 channel 3 input gates
• 2 channel 4 input gates

We will be using the 4 channel 2 input variants. Meaning that every IC holds 4 logic gates, each with 2 inputs and one output.

All IC's have the same pinout:

• Pin 1: GATE 1, INPUT X

• Pin 2: GATE 1, INPUT Y

• Pin 3: GATE 1, OUTPUT Z

• Pin 4: GATE 2, OUTPUT Z

• Pin 5: GATE 2, INPUT Y

• Pin 6: GATE 2, INPUT X

• Pin 7: VSS (ground)

• Pin 8: GATE 3, INPUT X

• Pin 9: GATE 3, INPUT Y

• Pin 10: GATE 3, OUTPUT Z

• Pin 11: GATE 4, OUTPUT Z

• Pin 12: GATE 4, INPUT Y

• Pin 13: GATE 4, INPUT X

• Pin 14: VDD (+6v)

You can choose between the following IC's:

CD4070BE:

Exclusive-OR gate

CD4070BE Datasheet

CD4077BE:

Exclusive-NOR gate

CD4077BE Datasheet

CD4071BE:

OR gate

CD4071BE datasheet

CD4001BE:

NOR gate

CD4001BE Datasheet

CD4011BE

NAND gate

CD4011BE Datasheet

CD4081BE

AND gate

CD4081BE Datasheet