2k+1
IEC odd-parity element
Element marked 2k+1 that is active when an odd number of inputs are active, as used for parity.
IEC
IEC · 2k
IEC even-parity element
Element marked 2k whose output is active when an even number of its inputs are active.
In plain English
What does IEC even-parity element mean?
The 2k additional drawing mark means the output is active when an even number of inputs, including none, are active. It is the multi-input generalisation of exclusive-NOR and is used in parity generation and checking for data words.
A simple example
On communication or memory logic drawings the even-parity element may feed a parity bit or compare a received parity bit. The drawing should indicate how many inputs are grouped, often with an input-line grouping or a bus notation, because the function depends on the full set.
What the drawings help you do
The element gives no information about word framing or when the parity result is sampled. Clocking and latching are separate elements.
This particular reference
Element marked 2k whose output is active when an even number of its inputs are active. The 2k+1 element is its complement and gives odd parity.
- Normally open / normally closed
- The contact state in the normal condition defined for the drawing.
- Signal
- Electrical information passed between devices, rather than necessarily the main power supply.
- Schematic
- A drawing showing function and connections rather than physical appearance.
Read the source: Overview of IEEE Standard 91-1984: explanation of logic symbols (SDYZ001A) · SN74LS280 — odd/even parity generation and checking
IEC · Rectangular element with the 2k general 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.
Shown as an independently authored educational illustration. Use the cited publication and drawing legend to verify the required drafting form.
Schematic · 2k
What it represents
The 2k qualifier means the output is active when an even number of inputs, including none, are active. It is the multi-input generalisation of exclusive-NOR and is used in parity generation and checking for data words.
On communication or memory logic drawings the even-parity element may feed a parity bit or compare a received parity bit. The drawing should indicate how many inputs are grouped, often with an input-line grouping or a bus notation, because the function depends on the full set.
The element gives no information about word framing or when the parity result is sampled. Clocking and latching are separate elements.
How to read it
- Count all inputs, including any shown by bus notation.
- Zero active inputs counts as even.
Information to show or reference
- Use 2k rather than =1 or = for parity.
- Group the input bus clearly.
- Show where the result is latched or compared.
A distinction that matters
The 2k+1 element is its complement and gives odd parity.
Sources you can follow
These public references support the explanation and provide further detail. Their graphics and downloadable files remain with their publishers.
Overview of IEEE Standard 91-1984: explanation of logic symbols (SDYZ001A)
Defines the 2k qualifier.
SN74LS280 — odd/even parity generation and checking
Manufacturer parity generator and checker documentation.
About this graphic
This illustration was authored independently by Elora Grid to explain the concept. It is not reproduced from a customer drawing, an official standard graphic or a manufacturer CAD file. Its correspondence to an exact IEC or IEEE symbol identifier has not been certified.
SVG and DXF downloads contain this original artwork. DXF uses unscaled drawing units; a GA envelope supplies no product dimensions, clearances or fabrication information. Original artwork is available under CC BY 4.0. Third-party references retain their own terms.
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