component
A1221LLHLT-T
Public Made by Adomby adom
Allegro MicroSystems, LLC Hall Sensor, SOT-23. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
main
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536
{
"schema_version": 1,
"type": "component",
"slug": "a1221llhlt-t",
"title": "A1221LLHLT-T",
"brief": "Allegro MicroSystems, LLC Hall Sensor, SOT-23. 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",
"sensors",
"a1221llhlt-t",
"factory-2.0.0",
"extractor-text"
],
"component": {
"mpn": "A1221LLHLT-T",
"manufacturer": "Allegro MicroSystems, LLC",
"package": "SOT-23",
"pin_count": 3,
"category": "Sensors",
"subcategory": "Hall Sensor",
"datasheet": "https://datasheet.lcsc.com/datasheet/pdf/37f3668ae4efafcb3302e7475e24c11d.pdf",
"parts": {
"symbol": "a1221llhlt-t.kicad_sym",
"footprint": "a1221llhlt-t.kicad_mod",
"model_3d": "a1221llhlt-t-hero.glb",
"model_3d_plain": "a1221llhlt-t-etched.glb",
"model_3d_step": "a1221llhlt-t-etched.step",
"model_3d_step_plain": "a1221llhlt-t.step",
"lbr": "a1221llhlt-t.lbr"
},
"distributor_links": {
"lcsc": "C696107",
"digikey": "620-1280-2-ND",
"mouser": "250-A1221LLHLT-T"
},
"distributor_check": {
"checked_at": "2026-10-31T12:40:44Z",
"source": "Component Ocean /api/assign-pns",
"digikey": {
"pn": "620-1280-2-ND",
"status": "found",
"lifecycle": "Active"
},
"mouser": {
"pn": "250-A1221LLHLT-T",
"status": "found"
}
},
"pins": [
{
"number": "1",
"name": "VCC",
"type": "power_in",
"description": "Connects power supply to chip; operating range 3 to 24 V (26.5 V absolute maximum), with a 0.1 µF bypass capacitor recommended close to the device."
},
{
"number": "2",
"name": "VOUT",
"type": "output",
"description": "Short-circuit protected open-drain output that sinks up to 25 mA continuous (current limit 30 to 60 mA) and goes low when B > BOP; off-state voltage up to 26 V."
},
{
"number": "3",
"name": "GND",
"type": "power_in",
"description": "Ground connection for the device."
}
],
"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",
"consensus_model": "claude-sonnet-5-5",
"consensus": "agreed",
"guards": "pin_guards 0.1: passed",
"guard_notes": [
"extractor flagged: The A1221LLHLT-T is sold in the LH package (3-pin SOT23W, a modified SOT-23), not a plain SOT-23. Th"
],
"pages_sent": 16,
"cost_usd": 0.1234,
"at": "2026-10-31T12:40:30"
},
"datasheet": {
"url": "https://datasheet.lcsc.com/datasheet/pdf/37f3668ae4efafcb3302e7475e24c11d.pdf",
"pages": 16,
"sha256": "b9c5a500fa2b3a36",
"source_tier": "lcsc"
},
"cad": "KiCad official (CC-BY-SA 4.0)",
"pins": {
"total": 3,
"described": 3,
"cites_pages": true,
"refuses_to_fabricate": true
}
},
"viewers": {
"symbol": "viewers/symbol.html",
"footprint": "viewers/footprint.html"
},
"models_3d": [
{
"file": "a1221llhlt-t.step",
"role": "plain",
"up": "Z",
"units": "mm",
"origin": "footprint origin = pad-pattern centre",
"seat": "z = 0",
"extents_mm": [
2.5,
3,
1.2
],
"zmin_mm": 0,
"centre_offset_mm": 0,
"footprint_binding": "identity",
"sha256": "dd5d1711204e1d8d26cd11490923bd84340820baa69538c385a4300ec2539bc0",
"checked": "2026-10-31",
"checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
},
{
"file": "a1221llhlt-t-etched.step",
"role": "eda",
"up": "Z",
"units": "mm",
"origin": "footprint origin = pad-pattern centre",
"seat": "z = 0",
"extents_mm": [
2.5,
3,
1.2
],
"zmin_mm": 0,
"centre_offset_mm": 0,
"footprint_binding": "identity",
"sha256": "e31c5d8fe5b5fffaeb6908105ba7a89d6defa7b0a77a00b607d2e1fca2f917d1",
"checked": "2026-10-31",
"checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
}
]
},
"metadata": {
"specs": {
"Manufacturer": "Allegro MicroSystems, LLC",
"Package": "SOT-23",
"Category": "Sensors",
"Pins": "3"
},
"appearance": {
"contacts": {
"quote": "through-hole mounting. Both packages are lead (Pb) free, with 100% matte-tin-plated leadframes.",
"page": 2,
"doc": "ds.pdf",
"plating": "tin"
},
"version": 1,
"datasheet_sha256": "b9c5a500fa2b3a367292f11d5a0649aed616d9427cfb37bcd218b5d0026f4634"
},
"characteristics": {
"version": 1,
"source": "datasheet",
"datasheet_sha256": "b9c5a500fa2b3a367292f11d5a0649aed616d9427cfb37bcd218b5d0026f4634",
"rows": [
{
"name": "Forward Supply Voltage",
"symbol": "VCC",
"kind": "absolute_maximum",
"unit": "V",
"min": null,
"typ": null,
"max": 26.5,
"conditions": "",
"source_page": 3,
"source": "datasheet"
},
{
"name": "Reverse Supply Voltage",
"symbol": "VRCC",
"kind": "absolute_maximum",
"unit": "V",
"min": -30,
"typ": null,
"max": null,
"conditions": "",
"source_page": 3,
"source": "datasheet"
},
{
"name": "Output Off Voltage",
"symbol": "VOUT",
"kind": "absolute_maximum",
"unit": "V",
"min": null,
"typ": null,
"max": 26,
"conditions": "",
"source_page": 3,
"source": "datasheet"
},
{
"name": "Continuous Output Current",
"symbol": "IOUT",
"kind": "absolute_maximum",
"unit": "mA",
"min": null,
"typ": null,
"max": 25,
"conditions": "",
"source_page": 3,
"source": "datasheet"
},
{
"name": "Reverse Output Current",
"symbol": "IROUT",
"kind": "absolute_maximum",
"unit": "mA",
"min": -50,
"typ": null,
"max": null,
"conditions": "",
"source_page": 3,
"source": "datasheet"
},
{
"name": "Operating Ambient Temperature",
"symbol": "TA",
"kind": "absolute_maximum",
"unit": "°C",
"min": -40,
"typ": null,
"max": 150,
"conditions": "Range L",
"source_page": 3,
"source": "datasheet"
},
{
"name": "Maximum Junction Temperature",
"symbol": "TJ(max)",
"kind": "absolute_maximum",
"unit": "°C",
"min": null,
"typ": null,
"max": 165,
"conditions": "",
"source_page": 3,
"source": "datasheet"
},
{
"name": "Maximum Junction Temperature",
"symbol": "TJ(max)",
"kind": "absolute_maximum",
"unit": "°C",
"min": null,
"typ": null,
"max": 175,
"conditions": "For 500 hours",
"source_page": 3,
"source": "datasheet"
},
{
"name": "Storage Temperature",
"symbol": "Tstg",
"kind": "absolute_maximum",
"unit": "°C",
"min": -65,
"typ": null,
"max": 170,
"conditions": "",
"source_page": 3,
"source": "datasheet"
},
{
"name": "Forward Supply Voltage",
"symbol": "VCC",
"kind": "electrical",
"unit": "V",
"min": 3,
"typ": null,
"max": 24,
"conditions": "Operating, TJ < 165°C",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Output Leakage Current",
"symbol": "IOUTOFF",
"kind": "electrical",
"unit": "µA",
"min": null,
"typ": null,
"max": 10,
"conditions": "VOUT = 24 V, B < BRP",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Output Saturation Voltage",
"symbol": "VOUT(SAT)",
"kind": "electrical",
"unit": "mV",
"min": null,
"typ": 185,
"max": 500,
"conditions": "IOUT = 20 mA, B > BOP",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Output Current Limit",
"symbol": "IOM",
"kind": "electrical",
"unit": "mA",
"min": 30,
"typ": null,
"max": 60,
"conditions": "B > BOP",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Power-On Time",
"symbol": "tPO",
"kind": "timing",
"unit": "µs",
"min": null,
"typ": null,
"max": 25,
"conditions": "VCC > 3.0 V, B < BRP(min) – 10 G, B > BOP(max) + 10 G",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Output Rise Time",
"symbol": "tr",
"kind": "timing",
"unit": "µs",
"min": null,
"typ": 0.2,
"max": 2,
"conditions": "RL = 820 Ω, CL = 20 pF",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Output Fall Time",
"symbol": "tf",
"kind": "timing",
"unit": "µs",
"min": null,
"typ": 0.1,
"max": 2,
"conditions": "RL = 820 Ω, CL = 20 pF",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Supply Current (On)",
"symbol": "ICC(ON)",
"kind": "electrical",
"unit": "mA",
"min": null,
"typ": null,
"max": 4,
"conditions": "B > BOP, VCC = 12 V",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Supply Current (Off)",
"symbol": "ICC(OFF)",
"kind": "electrical",
"unit": "mA",
"min": null,
"typ": null,
"max": 4,
"conditions": "B < BRP, VCC = 12 V",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Reverse Supply Current",
"symbol": "IRCC",
"kind": "electrical",
"unit": "mA",
"min": null,
"typ": null,
"max": -5,
"conditions": "VRCC = –20 V",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Supply Zener Clamp Voltage",
"symbol": "VZ",
"kind": "electrical",
"unit": "V",
"min": 28,
"typ": null,
"max": null,
"conditions": "ICC = 5 mA; TA = 25°C",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Operate Point (A1221)",
"symbol": "BOP",
"kind": "electrical",
"unit": "G",
"min": 15,
"typ": 50,
"max": 90,
"conditions": "A1221",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Release Point (A1221)",
"symbol": "BRP",
"kind": "electrical",
"unit": "G",
"min": -90,
"typ": -50,
"max": -15,
"conditions": "A1221",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Hysteresis (A1221)",
"symbol": "BHYS",
"kind": "electrical",
"unit": "G",
"min": 30,
"typ": 100,
"max": 180,
"conditions": "A1221, BOP – BRP",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Chopping Frequency",
"symbol": "fC",
"kind": "electrical",
"unit": "kHz",
"min": null,
"typ": 800,
"max": null,
"conditions": "",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Zener Impedance",
"symbol": "IZ",
"kind": "electrical",
"unit": "Ω",
"min": null,
"typ": 50,
"max": null,
"conditions": "ICC = 5 mA; TA = 25°C",
"source_page": 4,
"source": "datasheet"
},
{
"name": "Package Thermal Resistance",
"symbol": "RθJA",
"kind": "thermal",
"unit": "°C/W",
"min": null,
"typ": 228,
"max": null,
"conditions": "Package LH, 1-layer PCB with copper limited to solder pads",
"source_page": 5,
"source": "datasheet"
},
{
"name": "Package Thermal Resistance",
"symbol": "RθJA",
"kind": "thermal",
"unit": "°C/W",
"min": null,
"typ": 110,
"max": null,
"conditions": "Package LH, 2-layer PCB with 0.463 in.2 of copper area each side connected by thermal vias",
"source_page": 5,
"source": "datasheet"
}
]
}
},
"variants": [],
"sections": [
"hero",
"viewers",
"readme",
"breadcrumbs",
"info"
],
"discovery_triggers": [
"a1221llhlt-t"
],
"discovery_pitch": "A1221LLHLT-T (Allegro MicroSystems, LLC) 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",
"a1221llhlt-t.kicad_sym",
"a1221llhlt-t.kicad_mod",
"a1221llhlt-t.glb",
"a1221llhlt-t.step",
"a1221llhlt-t.lbr",
"docs/hero.png",
"docs/a1221llhlt-t-datasheet.pdf",
"viewers/symbol.html",
"viewers/footprint.html",
"a1221llhlt-t-hero.glb",
"a1221llhlt-t-hero.overlay.json",
"a1221llhlt-t-etched.glb"
],
"visibility": {
"public": true
}
}