Practical Electronics/IC/4068

The 4068 is a member of the 4000 Series CMOS range, and contains a single 8-input NAND gate, and, on some models the inverted output (i.e. an AND gate). The pinout diagram, given on the right, is the standard eight-input CMOS logic gate IC layout:

• Pin 7 is the ground supply (GND)
• Pin 14 is the positive supply (V_DD)
• Pins 2-5 and 9-12 are gate inputs for the gate
• Pin 1 and 13 are gate outputs. Pin 1 is not always available.
• Pin 6 and 8 are not connected.

The NAND gate gives a high output for any combination of inputs, except when all inputs are high. The AND gate only gives a high when all inputs are high.

$Q=\overline{A\cdot B\cdot C\cdot D\cdot E\cdot F\cdot G\cdot H}$

$\bar{Q}=A\cdot B\cdot C\cdot D\cdot E\cdot F\cdot G\cdot H$

This chip is widely available, and usually comes in a DIL-14 or SOIC-14 package.

An 8-input NAND gate is available as the TTL 7430, but no AND gate is available.