component
CD74AC257M
Public Made by Adomby adom
Texas Instruments Signal Switches, Multiplexers, Decoders, SOIC-16. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
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README.mdadded+53@@ -0,0 +1,53 @@+# CD74AC257M++**Texas Instruments** · Signal Switches, Multiplexers, Decoders · SOIC-16++CD74AC257M from Texas Instruments, in a SOIC-16. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.++## Pinout++| Pin | Name | Type | Function |+|---|---|---|---|+| 1 | S | input | Select input; routes channel I0 to output when low, channel I1 to output when high. |+| 2 | 1I0 | input | Channel 1 input 0; data input selected to 1Y output when select pin is low. |+| 3 | 1I1 | input | Channel 1 input 1; data input selected to 1Y output when select pin is high. |+| 4 | 1Y | tri_state | Channel 1 output; tri-state multiplexed output driven by selected input and controlled by output enable. |+| 5 | 2I0 | input | Channel 2 input 0; data input selected to 2Y output when select pin is low. |+| 6 | 2I1 | input | Channel 2 input 1; data input selected to 2Y output when select pin is high. |+| 7 | 2Y | tri_state | Channel 2 output; tri-state multiplexed output driven by selected input and controlled by output enable. |+| 8 | GND | power_in | Ground; reference voltage for all signal and power pins. |+| 9 | 3Y | tri_state | Channel 3 output; tri-state multiplexed output driven by selected input and controlled by output enable. |+| 10 | 3I1 | input | Channel 3 input 1; data input selected to 3Y output when select pin is high. |+| 11 | 3I0 | input | Channel 3 input 0; data input selected to 3Y output when select pin is low. |+| 12 | 4Y | tri_state | Channel 4 output; tri-state multiplexed output driven by selected input and controlled by output enable. |+| 13 | 4I1 | input | Channel 4 input 1; data input selected to 4Y output when select pin is high. |+| 14 | 4I0 | input | Channel 4 input 0; data input selected to 4Y output when select pin is low. |+| 15 | OE | input | Output enable, active low; when high forces all outputs to high impedance state regardless of inputs. |+| 16 | VCC | power_in | Positive power supply; 1.5V to 5.5V operating range for AC type, temperature range -55°C to 125°C. |++## Key specifications++| Parameter | Value |+|---|---|+| Manufacturer | Texas Instruments |+| Package | SOIC-16 |+| Category | Logic |+| Pins | 16 |++## CAD (KiCad official)++- Symbol: `CD74AC257M`+- Footprint: `Package_SO:SOIC-16_3.9x9.9mm_P1.27mm`+- 3D model: SOIC-16 (KiCad packages3D, STEP)+- 3D model files: `cd74ac257m-etched.step` / `cd74ac257m-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `cd74ac257m.step` / `cd74ac257m.glb` are the bare package body.++## Provenance++Data extracted from the manufacturer datasheet, not a distributor listing:++- **Datasheet:** [Texas Instruments datasheet](https://www.ti.com/cn/lit/gpn/cd74ac257) (29 pp, sha256 `f4d61e0b521229dd`, retrieved 2026-09-27, tier: lcsc)+- **Datasheet language:** Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.+- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.2`, primary `claude-haiku-4-5-20251001` (text), consensus `claude-sonnet-4-6` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.+- **CAD:** KiCad official libraries (CC-BY-SA 4.0).++[Datasheet PDF](docs/cd74ac257m-datasheet.pdf)
page.jsonadded+205@@ -0,0 +1,205 @@+{+ "slug": "cd74ac257m",+ "version": "0.1.0",+ "type": "component",+ "description": "Texas Instruments Signal Switches, Multiplexers, Decoders, SOIC-16. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",+ "tags": [+ "component",+ "logic",+ "cd74ac257m",+ "factory-2.0.0",+ "extractor-text"+ ],+ "dependencies": {},+ "hero": {+ "type": "image",+ "path": "docs/hero.png"+ },+ "files": [+ "page.json",+ "README.md",+ "cd74ac257m.kicad_sym",+ "cd74ac257m.kicad_mod",+ "cd74ac257m.glb",+ "cd74ac257m.step",+ "cd74ac257m.lbr",+ "docs/hero.png",+ "docs/cd74ac257m-datasheet.pdf",+ "viewers/symbol.html",+ "viewers/footprint.html"+ ],+ "component": {+ "mpn": "CD74AC257M",+ "manufacturer": "Texas Instruments",+ "package": "SOIC-16",+ "pin_count": 16,+ "category": "Logic",+ "subcategory": "Signal Switches, Multiplexers, Decoders",+ "datasheet": "https://www.ti.com/cn/lit/gpn/cd74ac257",+ "parts": {+ "symbol": "cd74ac257m.kicad_sym",+ "footprint": "cd74ac257m.kicad_mod",+ "model_3d": "cd74ac257m-etched.glb",+ "model_3d_plain": "cd74ac257m.glb",+ "model_3d_step": "cd74ac257m-etched.step",+ "model_3d_step_plain": "cd74ac257m.step",+ "lbr": "cd74ac257m.lbr"+ },+ "distributor_links": {+ "lcsc": "C1547195",+ "digikey": "296-4243-5-ND",+ "mouser": "595-CD74AC257M"+ },+ "distributor_check": {+ "checked_at": "2026-09-27T09:22:11Z",+ "source": "Component Ocean /api/assign-pns",+ "digikey": {+ "pn": "296-4243-5-ND",+ "status": "found",+ "lifecycle": "Obsolete"+ },+ "mouser": {+ "pn": "595-CD74AC257M",+ "status": "found",+ "lifecycle": "End of Life"+ }+ },+ "pins": [+ {+ "number": "1",+ "name": "S",+ "type": "input",+ "description": "Select input; routes channel I0 to output when low, channel I1 to output when high."+ },+ {+ "number": "2",+ "name": "1I0",+ "type": "input",+ "description": "Channel 1 input 0; data input selected to 1Y output when select pin is low."+ },+ {+ "number": "3",+ "name": "1I1",+ "type": "input",+ "description": "Channel 1 input 1; data input selected to 1Y output when select pin is high."+ },+ {+ "number": "4",+ "name": "1Y",+ "type": "tri_state",+ "description": "Channel 1 output; tri-state multiplexed output driven by selected input and controlled by output enable."+ },+ {+ "number": "5",+ "name": "2I0",+ "type": "input",+ "description": "Channel 2 input 0; data input selected to 2Y output when select pin is low."+ },+ {+ "number": "6",+ "name": "2I1",+ "type": "input",+ "description": "Channel 2 input 1; data input selected to 2Y output when select pin is high."+ },+ {+ "number": "7",+ "name": "2Y",+ "type": "tri_state",+ "description": "Channel 2 output; tri-state multiplexed output driven by selected input and controlled by output enable."+ },+ {+ "number": "8",+ "name": "GND",+ "type": "power_in",+ "description": "Ground; reference voltage for all signal and power pins."+ },+ {+ "number": "9",+ "name": "3Y",+ "type": "tri_state",+ "description": "Channel 3 output; tri-state multiplexed output driven by selected input and controlled by output enable."+ },+ {+ "number": "10",+ "name": "3I1",+ "type": "input",+ "description": "Channel 3 input 1; data input selected to 3Y output when select pin is high."+ },+ {+ "number": "11",+ "name": "3I0",+ "type": "input",+ "description": "Channel 3 input 0; data input selected to 3Y output when select pin is low."+ },+ {+ "number": "12",+ "name": "4Y",+ "type": "tri_state",+ "description": "Channel 4 output; tri-state multiplexed output driven by selected input and controlled by output enable."+ },+ {+ "number": "13",+ "name": "4I1",+ "type": "input",+ "description": "Channel 4 input 1; data input selected to 4Y output when select pin is high."+ },+ {+ "number": "14",+ "name": "4I0",+ "type": "input",+ "description": "Channel 4 input 0; data input selected to 4Y output when select pin is low."+ },+ {+ "number": "15",+ "name": "OE",+ "type": "input",+ "description": "Output enable, active low; when high forces all outputs to high impedance state regardless of inputs."+ },+ {+ "number": "16",+ "name": "VCC",+ "type": "power_in",+ "description": "Positive power supply; 1.5V to 5.5V operating range for AC type, temperature range -55°C to 125°C."+ }+ ],+ "provenance": {+ "extractor": "extract_pins 0.2",+ "factory_chain": {+ "factory": "2.0.0",+ "extractor": "extract_pins 0.2",+ "primary_model": "claude-haiku-4-5-20251001",+ "primary_mode": "text",+ "consensus_model": "claude-sonnet-4-6",+ "consensus": "agreed",+ "guards": "pin_guards 0.1: passed",+ "guard_notes": [],+ "pages_sent": 29,+ "cost_usd": 0.2876,+ "at": "2026-09-27T09:21:53"+ },+ "datasheet": {+ "url": "https://www.ti.com/cn/lit/gpn/cd74ac257",+ "pages": 29,+ "sha256": "f4d61e0b521229dd",+ "source_tier": "lcsc"+ },+ "cad": "KiCad official (CC-BY-SA 4.0)",+ "pins": {+ "total": 16,+ "described": 16,+ "cites_pages": true,+ "refuses_to_fabricate": true+ }+ },+ "viewers": {+ "symbol": "viewers/symbol.html",+ "footprint": "viewers/footprint.html"+ }+ },+ "visibility": "public",+ "org": "adom",+ "author": {+ "name": "Ray",+ "email": "[email protected]"+ }+}