# ANSI wired-AND connection

Canonical URL: https://eloragrid.ai/symbols/ansi-wired-and-connection
Publisher: Elora Grid
Updated: 2026-10-28
Lookup label: WIRED-AND
Drawing use: Schematic
Reference families: IEEE / ANSI, Manufacturer

## Symbol convention

Convention: IEEE / ANSI
Form: Open-collector outputs joined to a common pulled-up line
Distinctive-shape form as used in IEEE/ANSI-style schematics and manufacturer data books. Independent educational drawing; exact standard geometry and compliance are not asserted.

Several open-collector outputs joined on one pulled-up line, so any output pulling low makes the line low.

## In plain English

### What does ANSI wired-AND connection mean?

A wired-AND connection is formed by joining open-collector or open-drain outputs to a single line with one pull-up. The line is high only when every output is off, so in positive logic the result is the AND of the individual output states. Some schematics draw a small AND outline around the junction to make the implied function visible.

### A simple example

Shared interrupt lines, ready signals and I2C-style buses rely on this arrangement. A drawing should show every output on the net, the single pull-up, and the supply, because adding or removing a driver changes the logic and the pull-up current.

### What the drawings help you do

The connection only works with open-circuit outputs. Joining push-pull outputs in the same way causes contention and possible damage, so the output type of each gate must be checked.

### This particular reference

Several open-collector outputs joined on one pulled-up line, so any output pulling low makes the line low. A wired-OR uses open-emitter outputs with a pull-down; wired-AND uses open-collector outputs with a pull-up.

### Terms

- Terminal: An identified point where a conductor connects.
- Signal: Electrical information passed between devices, rather than necessarily the main power supply.
- Rating: A value stating the conditions for which equipment is specified.

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)
- [SNx4HC05 hex inverters with open-drain outputs](https://www.ti.com/lit/ds/symlink/sn74hc05.pdf)


## What it represents

A wired-AND connection is formed by joining open-collector or open-drain outputs to a single line with one pull-up. The line is high only when every output is off, so in positive logic the result is the AND of the individual output states. Some schematics draw a small AND outline around the junction to make the implied function visible.
Shared interrupt lines, ready signals and I2C-style buses rely on this arrangement. A drawing should show every output on the net, the single pull-up, and the supply, because adding or removing a driver changes the logic and the pull-up current.
The connection only works with open-circuit outputs. Joining push-pull outputs in the same way causes contention and possible damage, so the output type of each gate must be checked.

## How to read it

- Check that every joined output is open collector or open drain.
- There should be one pull-up for the whole net.

## Information to show or reference

- Show all contributing outputs on the shared net.
- Draw a single pull-up with its value and supply.
- Mark the open-circuit output type on each driver.

## Important distinction

A wired-OR uses open-emitter outputs with a pull-down; wired-AND uses open-collector outputs with a pull-up.

## Facts

- Required output type: Open collector or open drain
- Resulting function: AND in positive logic
- 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. States that open-collector outputs are capable of positive-logic wired-AND connection.
- [SNx4HC05 hex inverters with open-drain outputs](https://www.ti.com/lit/ds/symlink/sn74hc05.pdf) — Texas Instruments. Manufacturer open-drain output documentation.

## 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.