Understand the difference.

Compare the meaning, drawing context and source references of two entries. A similar graphic or shared abbreviation does not establish equivalence.

1

IEC

IEC NOT element (rectangular form)

The IEC inverter is a single-input element carrying the qualifier 1, meaning the one input must be active, together with a negation at the output. The result is that the output is active when the input is inactive. Data books often replace the circle with a polarity triangle to show an active-low output.

Drawing use

Schematic

Application

Logic & signals

Reference family

IEC / Manufacturer

Form evidence

Single-input element marked 1 with output negation. Qualifying-symbol and dependency conventions as explained in TI's public overview of IEEE Std 91-1984, which incorporates IEC 617-12 work. Independent educational drawing; not certified IEC geometry or an IEC database identifier. The counterpart is the matching functional concept; no equivalence of every detailed standard graphic is asserted.

A distinction that matters

A box marked 1 without output negation is a non-inverting buffer.

Full referenceAdd to legend

NOT

Symbols

Logic inverter

Produces the opposite logical state of its defined digital input.

Drawing use

Schematic

Application

Logic & signals

Reference family

Manufacturer

A distinction that matters

A digital NOT gate inverts a logic state; an inverting analogue amplifier changes a continuous signal with a gain relationship.

Full referenceAdd to legend

Original educational previews. Follow the source references on each full entry for the appropriate standard or selected product.