MAG-COMP
Digital magnitude comparator
Compares two digital words to provide the specified equality and magnitude indications.
Schematic
IEC · COMP
IEC magnitude comparator (COMP)
IEC COMP element comparing two binary words P and Q, with outputs for P>Q, P=Q and P<Q.
In plain English
What does IEC magnitude comparator (COMP) mean?
The IEC magnitude comparator is marked COMP. Its inputs are grouped as word P and word Q with binary weights, and its outputs are labelled P>Q, P=Q and P<Q. Cascading inputs carry the same labels in a separate group so that comparators can be chained for longer words.
A simple example
Digital comparators appear in set-point logic, address matching and limit checking. A reviewer should confirm the bit order of P and Q, because a swapped weight produces a comparison that is correct only for some values.
What the drawings help you do
The symbol does not indicate whether the comparison is for signed or unsigned numbers. Standard devices compare unsigned binary.
This particular reference
IEC COMP element comparing two binary words P and Q, with outputs for P>Q, P=Q and P<Q. An analogue voltage comparator compares two voltages, not binary words.
- 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) · CD74HC85 — digital magnitude comparators
IEC · Rectangular element with COMP qualifier and P, Q input groups
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.
Shown as an independently authored educational illustration. Use the cited publication and drawing legend to verify the required drafting form.
Schematic · COMP
What it represents
The IEC magnitude comparator is marked COMP. Its inputs are grouped as word P and word Q with binary weights, and its outputs are labelled P>Q, P=Q and P<Q. Cascading inputs carry the same labels in a separate group so that comparators can be chained for longer words.
Digital comparators appear in set-point logic, address matching and limit checking. A reviewer should confirm the bit order of P and Q, because a swapped weight produces a comparison that is correct only for some values.
The symbol does not indicate whether the comparison is for signed or unsigned numbers. Standard devices compare unsigned binary.
How to read it
- Check bit weights on both words.
- Cascade inputs are needed for words longer than one device.
Information to show or reference
- Group and weight the P and Q inputs.
- Label all three outputs.
- Show cascade connections.
A distinction that matters
An analogue voltage comparator compares two voltages, not binary words.
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)
Lists COMP as the magnitude comparator qualifier.
CD74HC85 — digital magnitude comparators
Magnitude comparator 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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