# IEC AND dependency (G)

Canonical URL: https://eloragrid.ai/symbols/iec-and-dependency-g
Publisher: Elora Grid
Updated: 2026-10-28
Lookup label: Gm
Drawing use: Schematic
Reference families: IEC, Manufacturer

## Symbol convention

Convention: IEC
Form: Affecting input labelled Gm with affected inputs or outputs labelled m
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.

Dependency label Gm: inputs or outputs carrying the number m are ANDed with the affecting G input.

## In plain English

### What does IEC AND dependency (G) mean?

In dependency notation, an input labelled G followed by a number is an affecting input. Every input or output labelled with the same number is ANDed with it. When the G input is at its internal 1 state the affected signals act normally; at its internal 0 state they are forced to 0. A bar over the number means the complement of the G input affects them.

### A simple example

G dependency lets a device symbol show gating relationships without drawing extra AND gates. It is common on multiplexers, gated clocks and register symbols in device data books, and a drafter copying such a symbol must keep the numbers intact or the meaning changes.

### What the drawings help you do

The label describes logic only. It does not tell you whether the gating causes glitches on a clock line or what setup time applies between G and the affected input.

### This particular reference

Dependency label Gm: inputs or outputs carrying the number m are ANDed with the affecting G input. V (OR) dependency imposes a 1 state when the affecting input is 1; G imposes a 0 state when the affecting input is 0.

### Terms

- Signal: Electrical information passed between devices, rather than necessarily the main power supply.
- Schematic: A drawing showing function and connections rather than physical appearance.

Concept diagram: Identify the device and form → Read the connections and state → Check the equipment reference
A guide to reading this reference. The original symbol illustration and its drawing notes appear below; these boxes are not a wiring diagram.

- [Overview of IEEE Standard 91-1984: explanation of logic symbols (SDYZ001A)](https://www.ti.com/lit/ml/sdyz001a/sdyz001a.pdf)


## What it represents

In dependency notation, an input labelled G followed by a number is an affecting input. Every input or output labelled with the same number is ANDed with it. When the G input is at its internal 1 state the affected signals act normally; at its internal 0 state they are forced to 0. A bar over the number means the complement of the G input affects them.
G dependency lets a device symbol show gating relationships without drawing extra AND gates. It is common on multiplexers, gated clocks and register symbols in device data books, and a drafter copying such a symbol must keep the numbers intact or the meaning changes.
The label describes logic only. It does not tell you whether the gating causes glitches on a clock line or what setup time applies between G and the affected input.

## How to read it

- Match each G number to every input or output carrying that number.
- A bar over the affected number means the complement of G applies.

## Information to show or reference

- Keep G numbers unique within a symbol.
- Label every affected terminal with the matching number.
- Avoid mixing G numbers with other dependency letters using the same number.

## Important distinction

V (OR) dependency imposes a 1 state when the affecting input is 1; G imposes a 0 state when the affecting input is 0.

## Facts

- Affecting input at 1: Permits action
- Affecting input at 0: Imposes 0 state
- Artwork scope: Original educational illustration; consult the applicable standard and the selected device documentation for the exact graphic

## Public references

- [Overview of IEEE Standard 91-1984: explanation of logic symbols (SDYZ001A)](https://www.ti.com/lit/ml/sdyz001a/sdyz001a.pdf) — Texas Instruments. Section on G (AND) dependency and summary table of dependency notation.

## Graphic scope

Independent original educational concept illustration by Elora Grid. Not a certified standards graphic or manufacturer footprint. Unitless; not to scale. Original artwork licence: https://creativecommons.org/licenses/by/4.0/. Publisher material is linked only.