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Digital Circuit 03 OR-gate

Explaination how an OR-gate works in the usual cmos technology.
The OR-gate is one of the three fundamental elements of digital electronics, together with the AND-gate and the inverter. It consists of three NMOS transistors and three PMOS transistors. One pair of NMOS and PMOS form an inverter, the rest forms an NOR-Gate. The output of the NOR is inverted to OR. That is why most integrated chips that form an OR, also have an output for the NOR: it simply does not need any more transistors, because the NOR is already created. So you need only one pin to carry out the NOR.

an OR-gate has two inputs and one output.

The images and descriptions of the circuit on this page are public domain. 

You may download it, copy it, modify it, distribute it, even if you do not cite the source.

Nevertheless, you might want to cite correctly:

Title=Digital Circuit 03 OR-gate

Author=Benedikt Sessler

Date=25.Sept 2020


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