{"schemaVersion":1,"slug":"iec-priority-encoder","name":"IEC priority encoder (HPRI/BIN)","kind":"symbol","abbreviation":"HPRI/BIN","aliases":["highest-priority encoder","HPRI/BIN coder","IEC priority encoder form"],"category":"logic-signals","drawingTypes":["Schematic"],"referenceFamilies":["IEC","Manufacturer"],"summary":"IEC coder marked HPRI/BIN that outputs the binary number of the highest-priority active input.","description":["A priority encoder is shown as an X/Y coder with the qualifier HPRI/BIN: highest priority in, binary out. Inputs are numbered by priority, and outputs carry binary weights. Additional outputs often signal that any input is active, which lets stages be cascaded.","On control drawings priority encoders reduce many alarm or request lines to a code, for example to identify the most important active fault for display. The input numbering must match the intended priority order.","The symbol does not state whether inputs are latched. If the encoder input is a momentary event, a latch stage is needed before it."],"readingNotes":["Higher input number normally means higher priority.","Look for group-select or any-active outputs used to cascade."],"drawingChecklist":["Number inputs in priority order.","Show output weights.","Show cascade connections."],"distinction":"A plain binary encoder assumes only one input active; HPRI resolves multiple active inputs.","facts":[{"label":"Qualifier","value":"HPRI/BIN"},{"label":"Function","value":"Encodes highest-priority active input"},{"label":"Artwork scope","value":"Original educational illustration; consult the applicable standard and the selected device documentation for the exact graphic"}],"references":[{"sourceId":"s28-ti-ieee91-logic-symbols","relevance":"Coder qualifiers, including code designations."},{"sourceId":"pub-electronics-ti-hc148","relevance":"Priority encoder documentation."}],"related":["priority-encoder","iec-binary-decoder","iec-code-converter"],"artwork":"s28-iec-priority-encoder","publishedOn":"2026-10-28","updatedOn":"2026-10-28","provenance":"independent-public-research","symbolVariant":{"convention":"IEC","form":"X/Y coder with HPRI/BIN qualifier","reference":"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.","counterpart":"priority-encoder"},"plainEnglish":{"title":"What does IEC priority encoder (HPRI/BIN) mean?","introduction":"A priority encoder is shown as an X/Y coder with the additional drawing mark HPRI/BIN: highest priority in, binary out. Inputs are numbered by priority, and outputs carry binary weights. Additional outputs often signal that any input is active, which lets stages be cascaded.","example":"On control drawings priority encoders reduce many alarm or request lines to a code, for example to identify the most important active fault for display. The input numbering must match the intended priority order.","drawings":"The symbol does not state whether inputs are latched. If the encoder input is a momentary event, a latch stage is needed before it.","terms":[{"name":"Signal","meaning":"Electrical information passed between devices, rather than necessarily the main power supply."},{"name":"Schematic","meaning":"A drawing showing function and connections rather than physical appearance."}],"diagram":"flow","steps":["Identify the device and form","Read the connections and state","Check the equipment reference"],"caption":"A guide to reading this reference. The original symbol illustration and its drawing notes appear below; these boxes are not a wiring diagram.","sources":[{"label":"Overview of IEEE Standard 91-1984: explanation of logic symbols (SDYZ001A)","url":"https://www.ti.com/lit/ml/sdyz001a/sdyz001a.pdf"},{"label":"SN74HC148 — priority encoding","url":"https://www.ti.com/lit/ds/symlink/sn74hc148.pdf"}],"detail":"IEC coder marked HPRI/BIN that outputs the binary number of the highest-priority active input. A plain binary encoder assumes only one input active; HPRI resolves multiple active inputs.","profileId":"reviewed-symbol-20261028"},"url":"https://eloragrid.ai/symbols/iec-priority-encoder","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/iec-priority-encoder.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"s28-ti-ieee91-logic-symbols","title":"Overview of IEEE Standard 91-1984: explanation of logic symbols (SDYZ001A)","publisher":"Texas Instruments","url":"https://www.ti.com/lit/ml/sdyz001a/sdyz001a.pdf","type":"manufacturer","scope":"Public explanation of rectangular logic symbols, general qualifiers, input and output qualifiers, dependency notation, bistable elements and coders, consistent with IEC 617-12 work.","checkedOn":"2026-10-28","reuse":"link-only","relevance":"Coder qualifiers, including code designations."},{"id":"pub-electronics-ti-hc148","title":"SN74HC148 — priority encoding","publisher":"Texas Instruments","url":"https://www.ti.com/lit/ds/symlink/sn74hc148.pdf","type":"manufacturer","scope":"Public device-function and terminal documentation used as an example of priority encoding. Example part numbers are manufacturer identifiers, not IEC/IEEE symbol IDs. Device ratings, pin numbering and availability remain in the selected product documentation.","checkedOn":"2026-10-14","reuse":"link-only","relevance":"Priority encoder documentation."}]}