ic pins

[laurent sixtooth]

I've seen circuits using ic but that ic have let's say 14 pin's but in schematic pins used are 10or 7 pins .so those other are not used or must be grounded that's where i dont understand.


THANKS

 

[Phasor]

Often, ICs have pins which are labelled "NC", or Not Connected. They have no electrical purpose, and you should not connect anything to these pins.

The reason they are there, is to enable the manufacturer to produce the IC in standard sizes, usually Dual In-Line (DIL). DIL chips most commonly come with 8, 14, 18, 28 or 40 pins.

 

[jnegowski]

Hi

power supply connections are not shown for each chip, and if the chip has one or more packages in it like a lm324 quadamp if one package is not used it is not shown on prints.

joe

 

[zevon8]

Perhaps you are refering to CMOS gate packages, where there are unused gates in a design? It is generally a good practice to tie the unused gate inputs to ground/Vcc to prevent unwanted oscillations and power dissapation or instability of the unused gates.