Understand the difference.

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

EN

IEC

IEC three-state buffer (rectangular form)

The three-state buffer is drawn as a 1 element with a small downward triangle inside the outline next to the output, and an EN input. When EN is at its internal 1 state the output follows the input; at its internal 0 state the output goes to its external high-impedance state while the internal logic state is retained.

Drawing use

Schematic

Application

Logic & signals

Reference family

IEC / Manufacturer

Form evidence

1 element with EN input and inverted-triangle three-state output qualifier. 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

An open-circuit output uses a diamond qualifier and has no high-impedance logic state of its own; the three-state triangle is different.

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3STATE

Symbols

Three-state logic buffer

A digital output stage that can drive logical states or enter its documented high-impedance state.

Drawing use

Schematic

Application

Logic & signals

Reference family

Manufacturer

A distinction that matters

High impedance differs from driving logical zero; disabled outputs still have device-specific leakage and voltage limits.

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