component

A1221LLHLT-T

Public Made by Adom

by adom

Allegro MicroSystems, LLC Hall Sensor, SOT-23. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.

componentsensorsa1221llhlt-tfactory-2.0.0extractor-text

Verified A1221LLHLT-T

by Ray · last 31 Oct 2026 · 1 record · files match
SymbolFootprint3D modelPins

Verification log 1 record

31 Oct 2026RayPublished by the parts factory: tier lcsc, 3 pinsfiles match
SymbolFootprint3D modelPinsfor all variants
  • ✓component-page-verify: PASS
  • ✓cad_props: Datasheet, MPN and distributor properties match page.json
  • ✓component: A1221LLHLT-T · SOT-23 · 3 pins
  • ✓copper: 3 copper pads, none touching another net
  • ✓datasheet: all 3 pin names found in the 16-page datasheet
  • ✓distributor: lcsc C696107, digikey 620-1280-2-ND, mouser 250-A1221LLHLT-T
  • ✓family: SOT-23
  • ✓files: 7 declared files present
  • ✓hero: docs/hero.png 4000x2500
  • ✓lbr: OK: /tmp/cpv-9qp0asip/x.lbr is a valid EAGLE .lbr with complete deviceset
  • ✓license: CC-BY-SA-4.0
  • ✓models_3d: 2 records
  • •package_fit (skip): no component.package_dims on the page: the model is unchecked against the datasheet drawing
  • ✓pads: 3 pins = 3 pads
  • ✓pose: 2 STEP(s) Z-up, seated, centred
  • ✓symbol: 3 pins agree
  • ✓visibility: public, source open
Evidencedatasheet
Verified files✓ a1221llhlt-t.kicad_sym✓ a1221llhlt-t.kicad_mod✓ a1221llhlt-t.step
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Generated by kicad-footprint-generator · KiCad file format 20260206
Name Last commit message Last updated
docs Publish 0.1.0 · Ray 2d ago
viewers a1221llhlt-t: viewers · Ray 2d ago
a1221llhlt-t-etched.glb Publish 0.1.0 · Ray 2d ago
a1221llhlt-t-etched.step a1221llhlt-t: factory component page (tier=lcsc) · Ray 2d ago
a1221llhlt-t-hero.glb a1221llhlt-t: hero GLB from the etched model (keeps the MPN mark) · Ray 2d ago
a1221llhlt-t-hero.overlay.json Publish 0.1.0 · Ray 2d ago
a1221llhlt-t.glb Publish 0.1.0 · Ray 2d ago
a1221llhlt-t.kicad_mod Publish 0.1.0 · Ray 2d ago
a1221llhlt-t.kicad_sym Publish 0.1.0 · Ray 2d ago
a1221llhlt-t.lbr Publish 0.1.0 · Ray 2d ago
a1221llhlt-t.step Publish 0.1.0 · Ray 2d ago
package.json Publish 0.1.0 · Ray 2d ago
page.json Set visibility: public · Ray 2d ago
README.md Publish 0.1.0 · Ray 2d ago
verification.json Verified: Published by the parts factory: tier lcsc, 3 pins · Ray 2d ago

A1221LLHLT-T

Allegro MicroSystems, LLC · Hall Sensor · SOT-23

A1221LLHLT-T from Allegro MicroSystems, LLC, in a SOT-23. 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 VCC power_in 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.
2 VOUT output 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.
3 GND power_in Ground connection for the device.

Key specifications

Parameter Value
Manufacturer Allegro MicroSystems, LLC
Package SOT-23
Category Sensors
Pins 3

Electrical characteristics

Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).

Parameter Symbol Min Typ Max Unit Conditions Page
Forward Supply Voltage VCC 26.5 V 3
Reverse Supply Voltage VRCC -30 V 3
Output Off Voltage VOUT 26 V 3
Continuous Output Current IOUT 25 mA 3
Reverse Output Current IROUT -50 mA 3
Operating Ambient Temperature TA -40 150 °C Range L 3
Maximum Junction Temperature TJ(max) 165 °C 3
Maximum Junction Temperature TJ(max) 175 °C For 500 hours 3
Storage Temperature Tstg -65 170 °C 3
Forward Supply Voltage VCC 3 24 V Operating, TJ < 165°C 4
Output Leakage Current IOUTOFF 10 µA VOUT = 24 V, B < BRP 4
Output Saturation Voltage VOUT(SAT) 185 500 mV IOUT = 20 mA, B > BOP 4
Output Current Limit IOM 30 60 mA B > BOP 4
Power-On Time tPO 25 µs VCC > 3.0 V, B < BRP(min), 10 G, B > BOP(max) + 10 G 4
Output Rise Time tr 0.2 2 µs RL = 820 Ω, CL = 20 pF 4
Output Fall Time tf 0.1 2 µs RL = 820 Ω, CL = 20 pF 4
Supply Current (On) ICC(ON) 4 mA B > BOP, VCC = 12 V 4
Supply Current (Off) ICC(OFF) 4 mA B < BRP, VCC = 12 V 4
Reverse Supply Current IRCC -5 mA VRCC = -20 V 4
Supply Zener Clamp Voltage VZ 28 V ICC = 5 mA; TA = 25°C 4
Operate Point (A1221) BOP 15 50 90 G A1221 4
Release Point (A1221) BRP -90 -50 -15 G A1221 4
Hysteresis (A1221) BHYS 30 100 180 G A1221, BOP, BRP 4
Chopping Frequency fC 800 kHz 4
Zener Impedance IZ 50 Ω ICC = 5 mA; TA = 25°C 4
Package Thermal Resistance RθJA 228 °C/W Package LH, 1-layer PCB with copper limited to solder pads 5
Package Thermal Resistance RθJA 110 °C/W Package LH, 2-layer PCB with 0.463 in.2 of copper area each side connected by thermal vias 5

Materials and finish

As the datasheet states them (page.json metadata.appearance; the 3D model's colours follow it).

Part Material Colour / plating Datasheet says Page
contacts tin through-hole mounting. Both packages are lead (Pb) free, with 100% matte-tin-plated leadframes. 2

CAD (KiCad official)

  • Symbol: A1221LLHLT-T
  • Footprint: Package_TO_SOT_SMD:SOT-23
  • 3D model: SOT-23 (KiCad packages3D, STEP)
  • 3D model files: a1221llhlt-t-etched.step / a1221llhlt-t-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); a1221llhlt-t.step / a1221llhlt-t.glb are the bare package body.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Allegro MicroSystems, LLC datasheet (16 pp, sha256 b9c5a500fa2b3a36, retrieved 2026-10-31, tier: lcsc)
  • Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-sonnet-5-5 (text), consensus claude-sonnet-5-5 (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