Side-by-side reference

Understand the difference.

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

First referenceCompare with

LDR

IEEE / ANSI

ANSI/IEEE light-dependent resistor symbol

The light-dependent resistor form identifies a resistive component affected by illumination. Its sensing modifier describes the physical influence rather than a new electrical terminal, while the surrounding circuit translates the resistance change into a usable signal.

Drawing use: SLD / Schematic
Application: Electronic components
Reference family: IEEE / ANSI / Manufacturer
Form evidence: Autodesk IEEE-oriented Resistive Components functional form. Autodesk explicitly publishes this block under IEEE Symbol Preview. The counterpart is the matching functional concept; no equivalence of every detailed standard graphic is asserted.

A distinction that matters

An LDR changes resistance; a photodiode has a semiconductor junction and different measurement behaviour.

Full reference

LDR

Symbols

Light-dependent resistor

A light-dependent resistor changes resistance according to illumination. The schematic places the sensing element in its actual electrical network and the equipment detail identifies the illumination conditions.

Drawing use: SLD / Schematic
Application: Control circuits
Reference family: IEC / Manufacturer

A distinction that matters

An LDR changes resistance; a photodiode produces a different semiconductor sensing response.

Full reference

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