component
0437.250WR
Public Made by Adomby adom
Littelfuse Disposable Fuses, 1206. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
main
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480
{
"schema_version": 1,
"type": "component",
"slug": "0437-250wr",
"title": "0437.250WR",
"brief": "Littelfuse Disposable Fuses, 1206. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",
"version": "0.1.0",
"license": "CC-BY-SA-4.0",
"tags": [
"component",
"circuit protection",
"0437.250wr",
"factory-2.0.0",
"extractor-text"
],
"component": {
"mpn": "0437.250WR",
"manufacturer": "Littelfuse",
"package": "1206",
"pin_count": 2,
"category": "Circuit Protection",
"subcategory": "Disposable Fuses",
"datasheet": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588910096138690560",
"parts": {
"symbol": "0437-250wr.kicad_sym",
"footprint": "0437-250wr.kicad_mod",
"model_3d": "0437-250wr-hero.glb",
"model_3d_plain": "0437-250wr-etched.glb",
"model_3d_step": "0437-250wr-etched.step",
"model_3d_step_plain": "0437-250wr.step",
"lbr": "0437-250wr.lbr"
},
"distributor_links": {
"lcsc": "C206951"
},
"distributor_check": {
"checked_at": "2026-10-17T14:30:51Z",
"source": "Component Ocean /api/assign-pns",
"digikey": {
"pn": null,
"status": "quota"
},
"mouser": {
"pn": null,
"status": "quota"
}
},
"pins": [
{
"number": "1",
"name": "1",
"type": "passive",
"description": "Fuse terminal 1 (Ag/Ni/Sn end termination); non-polarized, 250mA fast-acting, rated 125 V AC/DC with 50 A interrupting rating."
},
{
"number": "2",
"name": "2",
"type": "passive",
"description": "Fuse terminal 2 (Ag/Ni/Sn end termination); non-polarized, interchangeable with terminal 1, nominal resistance 2.290 ohms."
}
],
"provenance": {
"extractor": "extract_pins 0.3",
"factory_chain": {
"factory": "2.0.0",
"extractor": "extract_pins 0.3",
"primary_model": "claude-sonnet-5-5",
"primary_mode": "text+vision",
"consensus_model": "claude-opus-5-5",
"consensus": "agreed",
"guards": "pin_guards 0.1: passed",
"guard_notes": [
"extractor flagged: The datasheet drawing shows two end terminations with no pin numbers printed; numbers 1 and 2 are as",
"vision extraction: provenance cannot be text-verified; needs consensus"
],
"pages_sent": 3,
"cost_usd": 0.1126,
"at": "2026-10-17T14:29:01"
},
"datasheet": {
"url": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588910096138690560",
"pages": 3,
"sha256": "4118dc56d128f864",
"source_tier": "lcsc"
},
"cad": "KiCad official (CC-BY-SA 4.0)",
"pins": {
"total": 2,
"described": 2,
"cites_pages": true,
"refuses_to_fabricate": true
}
},
"viewers": {
"symbol": "viewers/symbol.html",
"footprint": "viewers/footprint.html"
},
"models_3d": [
{
"file": "0437-250wr.step",
"role": "plain",
"up": "Z",
"units": "mm",
"origin": "footprint origin = pad-pattern centre",
"seat": "z = 0",
"extents_mm": [
3.2,
1.6,
0.55
],
"zmin_mm": 0,
"centre_offset_mm": 0,
"footprint_binding": "identity",
"sha256": "5e6dcbe286696143d35a8ea37d91eef4b54ff3d1bd7c2c2b4dedda83d3f8e203",
"checked": "2026-10-17",
"checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
},
{
"file": "0437-250wr-etched.step",
"role": "eda",
"up": "Z",
"units": "mm",
"origin": "footprint origin = pad-pattern centre",
"seat": "z = 0",
"extents_mm": [
3.2,
1.6,
0.55
],
"zmin_mm": 0,
"centre_offset_mm": 0,
"footprint_binding": "identity",
"sha256": "5e2fcf1552e52df3d3a3fcd7f9b9c4f0cec47e1c4349b97a8fca2cae39bac968",
"checked": "2026-10-17",
"checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
}
]
},
"metadata": {
"specs": {
"Manufacturer": "Littelfuse",
"Package": "1206",
"Category": "Circuit Protection",
"Pins": "2"
},
"appearance": {
"contacts": {
"quote": "Terminations: Ag / Ni / Sn (100% Lead-free) Element Cover Coating: Ceramic/Lead-free",
"page": 3,
"doc": "ds.pdf",
"plating": "tin"
},
"version": 1,
"datasheet_sha256": "4118dc56d128f864276a6cd630b009a9b0f2c0392c3afd2cd0b20face85d3ff0"
},
"characteristics": {
"version": 1,
"source": "datasheet",
"datasheet_sha256": "4118dc56d128f864276a6cd630b009a9b0f2c0392c3afd2cd0b20face85d3ff0",
"rows": [
{
"name": "Operating temperature",
"symbol": "",
"kind": "recommended_operating",
"unit": "ºC",
"min": -55,
"typ": null,
"max": 150,
"conditions": "",
"source_page": 1,
"source": "datasheet"
},
{
"name": "Opening time, 100% of ampere rating (250mA–8A)",
"symbol": "",
"kind": "timing",
"unit": "hours",
"min": 4,
"typ": null,
"max": null,
"conditions": "100% of rating, 250mA–8A, at 25ºC",
"source_page": 1,
"source": "datasheet"
},
{
"name": "Opening time, 350% of ampere rating (250mA–500mA)",
"symbol": "",
"kind": "timing",
"unit": "seconds",
"min": null,
"typ": null,
"max": 5,
"conditions": "350% of rating, 250mA–500mA, at 25ºC",
"source_page": 1,
"source": "datasheet"
},
{
"name": "Max. voltage rating",
"symbol": "",
"kind": "absolute_maximum",
"unit": "V",
"min": null,
"typ": null,
"max": 125,
"conditions": "Amp code .250 (250mA) row",
"source_page": 1,
"source": "datasheet"
},
{
"name": "Interrupting rating",
"symbol": "",
"kind": "absolute_maximum",
"unit": "A",
"min": null,
"typ": null,
"max": 50,
"conditions": "@ 125 V AC/DC",
"source_page": 1,
"source": "datasheet"
},
{
"name": "Continuous operation current",
"symbol": "",
"kind": "recommended_operating",
"unit": "% rated current",
"min": null,
"typ": null,
"max": 80,
"conditions": "Continuous operation, recommended",
"source_page": 1,
"source": "datasheet"
},
{
"name": "Nominal resistance",
"symbol": "",
"kind": "electrical",
"unit": "Ohms",
"min": null,
"typ": 2.29,
"max": null,
"conditions": "Measured with <10% rated current",
"source_page": 1,
"source": "datasheet"
},
{
"name": "Nominal melting I2t",
"symbol": "",
"kind": "electrical",
"unit": "A2Sec.",
"min": null,
"typ": 0.003,
"max": null,
"conditions": "",
"source_page": 1,
"source": "datasheet"
},
{
"name": "Nominal voltage drop at rated current",
"symbol": "",
"kind": "electrical",
"unit": "V",
"min": null,
"typ": 0.78,
"max": null,
"conditions": "At rated current, after temperature has stabilized",
"source_page": 1,
"source": "datasheet"
},
{
"name": "Nominal power dissipation at rated current",
"symbol": "",
"kind": "electrical",
"unit": "W",
"min": null,
"typ": 0.195,
"max": null,
"conditions": "At rated current",
"source_page": 1,
"source": "datasheet"
},
{
"name": "Reflow preheat temperature min (Ts(min))",
"symbol": "Ts(min)",
"kind": "thermal",
"unit": "ºC",
"min": 150,
"typ": null,
"max": null,
"conditions": "Pb-free reflow, pre-heat",
"source_page": 2,
"source": "datasheet"
},
{
"name": "Reflow preheat temperature max (Ts(max))",
"symbol": "Ts(max)",
"kind": "thermal",
"unit": "ºC",
"min": null,
"typ": null,
"max": 200,
"conditions": "Pb-free reflow, pre-heat",
"source_page": 2,
"source": "datasheet"
},
{
"name": "Reflow preheat time (ts)",
"symbol": "ts",
"kind": "timing",
"unit": "seconds",
"min": 60,
"typ": null,
"max": 180,
"conditions": "Pre-heat, Ts(min) to Ts(max)",
"source_page": 2,
"source": "datasheet"
},
{
"name": "Reflow time above liquidus (tL)",
"symbol": "tL",
"kind": "timing",
"unit": "seconds",
"min": 60,
"typ": null,
"max": 150,
"conditions": "Reflow, Pb-free",
"source_page": 2,
"source": "datasheet"
},
{
"name": "Peak temperature (TP)",
"symbol": "TP",
"kind": "thermal",
"unit": "ºC",
"min": null,
"typ": null,
"max": 260,
"conditions": "Pb-free reflow; printed as 260+0/-5 °C",
"source_page": 2,
"source": "datasheet"
},
{
"name": "Time within 5°C of actual peak temperature (tp)",
"symbol": "tp",
"kind": "timing",
"unit": "seconds",
"min": 10,
"typ": null,
"max": 30,
"conditions": "Within 5°C of actual peak temperature",
"source_page": 2,
"source": "datasheet"
},
{
"name": "Average ramp-up rate (TL to peak)",
"symbol": "",
"kind": "timing",
"unit": "°C/second",
"min": null,
"typ": null,
"max": 3,
"conditions": "Liquidus (TL) to peak",
"source_page": 2,
"source": "datasheet"
},
{
"name": "TS(max) to TL ramp-up rate",
"symbol": "",
"kind": "timing",
"unit": "°C/second",
"min": null,
"typ": null,
"max": 5,
"conditions": "TS(max) to TL",
"source_page": 2,
"source": "datasheet"
},
{
"name": "Ramp-down rate",
"symbol": "",
"kind": "timing",
"unit": "°C/second",
"min": null,
"typ": null,
"max": 6,
"conditions": "Peak to cooldown",
"source_page": 2,
"source": "datasheet"
},
{
"name": "Time 25°C to peak temperature",
"symbol": "",
"kind": "timing",
"unit": "minutes",
"min": null,
"typ": null,
"max": 8,
"conditions": "25°C to peak temperature (TP)",
"source_page": 2,
"source": "datasheet"
},
{
"name": "Maximum soldering temperature",
"symbol": "",
"kind": "absolute_maximum",
"unit": "ºC",
"min": null,
"typ": null,
"max": 260,
"conditions": "Pb-free reflow; 'Do not exceed 260°C'",
"source_page": 2,
"source": "datasheet"
},
{
"name": "Wave soldering temperature",
"symbol": "",
"kind": "absolute_maximum",
"unit": "ºC",
"min": null,
"typ": null,
"max": 260,
"conditions": "Wave soldering",
"source_page": 2,
"source": "datasheet"
},
{
"name": "Wave soldering time",
"symbol": "",
"kind": "timing",
"unit": "seconds",
"min": null,
"typ": null,
"max": 10,
"conditions": "Wave soldering at 260°C",
"source_page": 2,
"source": "datasheet"
}
]
}
},
"variants": [],
"sections": [
"hero",
"viewers",
"readme",
"breadcrumbs",
"info"
],
"discovery_triggers": [
"0437.250wr"
],
"discovery_pitch": "0437.250WR (Littelfuse) component page: datasheet pinout, KiCad symbol, footprint and 3D.",
"author": {
"name": "Ray",
"email": "[email protected]"
},
"dependencies": {},
"hero": {
"type": "image",
"path": "docs/hero.png"
},
"files": [
"page.json",
"README.md",
"0437-250wr.kicad_sym",
"0437-250wr.kicad_mod",
"0437-250wr.glb",
"0437-250wr.step",
"0437-250wr.lbr",
"docs/hero.png",
"docs/0437-250wr-datasheet.pdf",
"viewers/symbol.html",
"viewers/footprint.html",
"0437-250wr-hero.glb",
"0437-250wr-hero.overlay.json",
"0437-250wr-etched.glb"
],
"visibility": {
"public": true
}
}