Question

where we use 2n2222 transistor.

Answer 1

The 2N2222 is considered a very common transistor, and is used as an exemplar of an NPN transistor. It is frequently used as a small-signal transistor, and it remains a small general purpose transistor of enduring popularity. The 2N2222 was part of a family of devices described by Motorola at a 1962 IRE convention.

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