TMI8420

{
  "schema_version": 1,
  "type": "component",
  "slug": "tmi8420",
  "title": "TMI8420",
  "brief": "TMI Stepper Motor Driver, HTSSOP-28. 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",
    "motor driver ics",
    "tmi8420",
    "factory-2.0.0",
    "extractor-text"
  ],
  "component": {
    "mpn": "TMI8420",
    "manufacturer": "TMI",
    "package": "HTSSOP-28",
    "pin_count": 29,
    "category": "Motor Driver ICs",
    "subcategory": "Stepper Motor Driver",
    "datasheet": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8589836842058354688",
    "parts": {
      "symbol": "tmi8420.kicad_sym",
      "footprint": "tmi8420.kicad_mod",
      "model_3d": "tmi8420-hero.glb",
      "model_3d_plain": "tmi8420-etched.glb",
      "model_3d_step": "tmi8420-etched.step",
      "model_3d_step_plain": "tmi8420.step",
      "lbr": "tmi8420.lbr"
    },
    "distributor_links": {
      "lcsc": "C5259221"
    },
    "distributor_check": {
      "checked_at": "2026-10-18T22:14:22Z",
      "source": "Component Ocean /api/assign-pns",
      "digikey": {
        "pn": null,
        "status": "quota"
      },
      "mouser": {
        "pn": null,
        "status": "quota"
      }
    },
    "pins": [
      {
        "number": "1",
        "name": "CP1",
        "type": "bidirectional",
        "description": "Charge-pump flying-capacitor node; a 0.01 µF ceramic capacitor is connected between CP1 and CP2."
      },
      {
        "number": "2",
        "name": "CP2",
        "type": "bidirectional",
        "description": "Charge-pump flying-capacitor node; a 0.01 µF ceramic capacitor is connected between CP2 and CP1."
      },
      {
        "number": "3",
        "name": "VCP",
        "type": "bidirectional",
        "description": "Charge-pump output; a 0.1 µF ceramic capacitor is connected between VCP and VM."
      },
      {
        "number": "4",
        "name": "VMA",
        "type": "power_in",
        "description": "Motor supply for H-bridges A and B; recommended operating range 8.0 V to 45 V, with a 0.1 µF capacitor to GND plus bulk capacitance, and both VM pins must be on the same supply."
      },
      {
        "number": "5",
        "name": "AOUT1",
        "type": "output",
        "description": "Output pin 1 of H-bridge A, with each H-bridge output rated for up to 2.5 A."
      },
      {
        "number": "6",
        "name": "ISENA",
        "type": "bidirectional",
        "description": "Bridge A ground/current-sense terminal, to be connected to ground or to the bridge A current-sense resistor to ground."
      },
      {
        "number": "7",
        "name": "AOUT2",
        "type": "output",
        "description": "Output pin 2 of H-bridge A, with each H-bridge output rated for up to 2.5 A."
      },
      {
        "number": "8",
        "name": "BOUT2",
        "type": "output",
        "description": "Output pin 2 of H-bridge B, with each H-bridge output rated for up to 2.5 A."
      },
      {
        "number": "9",
        "name": "ISENB",
        "type": "bidirectional",
        "description": "Bridge B ground/current-sense terminal, to be connected to ground or to the bridge B current-sense resistor to ground."
      },
      {
        "number": "10",
        "name": "BOUT1",
        "type": "output",
        "description": "Output pin 1 of H-bridge B, with each H-bridge output rated for up to 2.5 A."
      },
      {
        "number": "11",
        "name": "VMB",
        "type": "power_in",
        "description": "Motor supply for H-bridges A and B; recommended operating range 8.0 V to 45 V, and must be connected to the same supply as VMA."
      },
      {
        "number": "12",
        "name": "AVREF",
        "type": "input",
        "description": "External reference setting bridge A winding current; normally tied to BVREF and may connect to V3P3OUT, with recommended range 1 V to 3.5 V."
      },
      {
        "number": "13",
        "name": "BVREF",
        "type": "input",
        "description": "External reference setting bridge B winding current; normally tied to AVREF and may connect to V3P3OUT, with recommended range 1 V to 3.5 V."
      },
      {
        "number": "14",
        "name": "GND",
        "type": "power_in",
        "description": "Ground pin of the device."
      },
      {
        "number": "15",
        "name": "V3P3OUT",
        "type": "power_out",
        "description": "3.3 V LDO output with a load capability of 10 mA per the recommended operating conditions."
      },
      {
        "number": "16",
        "name": "nRESET",
        "type": "input",
        "description": "Active-low reset input that initializes the indexer logic and disables the H-bridge outputs, with an internal pull-down."
      },
      {
        "number": "17",
        "name": "nSLEEP",
        "type": "input",
        "description": "Logic high enables the device and logic low puts it into low-power sleep mode, with an internal pull-down."
      },
      {
        "number": "18",
        "name": "nFAULT",
        "type": "output",
        "description": "Open-drain output that is pulled low when a fault occurs."
      },
      {
        "number": "19",
        "name": "DECAY",
        "type": "input",
        "description": "Decay-mode select: low selects slow decay, open selects mixed decay, and high selects fast decay."
      },
      {
        "number": "20",
        "name": "DIR",
        "type": "input",
        "description": "Logic input whose voltage level sets the step direction, with an internal pull-down."
      },
      {
        "number": "21",
        "name": "nENBL",
        "type": "input",
        "description": "Logic high disables device outputs and indexer operation, logic low enables them, with an internal pull-down."
      },
      {
        "number": "22",
        "name": "STEP",
        "type": "input",
        "description": "A rising edge advances the indexer to the next step, with an internal pull-down."
      },
      {
        "number": "23",
        "name": "NC",
        "type": "unconnected",
        "description": "No connection."
      },
      {
        "number": "24",
        "name": "MODE0",
        "type": "input",
        "description": "Step-mode select bit 0 (with MODE1 and MODE2) for full, 1/2, 1/4, 1/8, 1/16 or 1/32 step, with an internal pull-down."
      },
      {
        "number": "25",
        "name": "MODE1",
        "type": "input",
        "description": "Step-mode select bit 1 (with MODE0 and MODE2) for full, 1/2, 1/4, 1/8, 1/16 or 1/32 step, with an internal pull-down."
      },
      {
        "number": "26",
        "name": "MODE2",
        "type": "input",
        "description": "Step-mode select bit 2 (with MODE0 and MODE1) for full, 1/2, 1/4, 1/8, 1/16 or 1/32 step, with an internal pull-down."
      },
      {
        "number": "27",
        "name": "nHOME",
        "type": "output",
        "description": "Open-drain output that is pulled low when the motor reaches the home position."
      },
      {
        "number": "28",
        "name": "GND",
        "type": "power_in",
        "description": "Ground pin of the device."
      },
      {
        "number": "29",
        "name": "EP",
        "type": "passive",
        "description": "Exposed pad (from the footprint; not named in the datasheet pin table)."
      }
    ],
    "provenance": {
      "extractor": "extract_pins 0.3",
      "factory_chain": {
        "factory": "2.0.0",
        "extractor": "extract_pins 0.3",
        "primary_model": "claude-haiku-5-5",
        "primary_mode": "text",
        "consensus_model": "claude-sonnet-5-5",
        "consensus": "agreed",
        "guards": "pin_guards 0.1: passed",
        "guard_notes": [
          "extractor flagged: Open-drain outputs nFAULT and nHOME are typed as 'output' because the KiCad class list has no open-d; CP1, CP2, VCP, ISENA and ISENB are marked 'I/O' in the datasheet and are mapped to 'bidirectional'; ; Pin 23 is labeled NC (no connection) in the datasheet and is typed 'unconnected'.",
          "exposed pad 29 added from the footprint"
        ],
        "pages_sent": 20,
        "cost_usd": 0.0782,
        "at": "2026-10-18T22:14:09"
      },
      "datasheet": {
        "url": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8589836842058354688",
        "pages": 20,
        "sha256": "0b8e8cbabaf3877f",
        "source_tier": "lcsc"
      },
      "cad": "KiCad official (CC-BY-SA 4.0)",
      "pins": {
        "total": 29,
        "described": 29,
        "cites_pages": true,
        "refuses_to_fabricate": true
      }
    },
    "viewers": {
      "symbol": "viewers/symbol.html",
      "footprint": "viewers/footprint.html"
    },
    "models_3d": [
      {
        "file": "tmi8420.step",
        "role": "plain",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "z = 0",
        "extents_mm": [
          7.2,
          9.7,
          1.05
        ],
        "zmin_mm": 0,
        "centre_offset_mm": 0,
        "footprint_binding": "identity",
        "sha256": "ff242f1d3be9d09e7f929707a2c5b1ee974a4f882053b04bcdb1cd2cb21223ef",
        "checked": "2026-10-18",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      },
      {
        "file": "tmi8420-etched.step",
        "role": "eda",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "z = 0",
        "extents_mm": [
          7.2,
          9.7,
          1.05
        ],
        "zmin_mm": 0,
        "centre_offset_mm": 0,
        "footprint_binding": "identity",
        "sha256": "d490242d1f12ebe1a257d1cf82345198932f624b4055533c12463864ca1c2560",
        "checked": "2026-10-18",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      }
    ]
  },
  "metadata": {
    "specs": {
      "Manufacturer": "TMI",
      "Package": "HTSSOP-28",
      "Category": "Motor Driver ICs",
      "Pins": "29"
    },
    "characteristics": {
      "version": 1,
      "source": "datasheet",
      "datasheet_sha256": "0b8e8cbabaf3877f3f3ef2a3155332bf584a85dc5ca6d69274775b10f5362d74",
      "rows": [
        {
          "name": "Supply voltage",
          "symbol": "VM",
          "kind": "absolute_maximum",
          "unit": "V",
          "min": -0.3,
          "typ": null,
          "max": 48,
          "conditions": "",
          "source_page": 2,
          "source": "datasheet"
        },
        {
          "name": "Logic input voltage",
          "symbol": "VIN",
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          "unit": "V",
          "min": -0.3,
          "typ": null,
          "max": 7,
          "conditions": "",
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          "source": "datasheet"
        },
        {
          "name": "Reference input voltage",
          "symbol": "VVREF",
          "kind": "absolute_maximum",
          "unit": "V",
          "min": -0.3,
          "typ": null,
          "max": 4,
          "conditions": "",
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        },
        {
          "name": "Output continuous current",
          "symbol": "IOUT",
          "kind": "absolute_maximum",
          "unit": "A",
          "min": 0,
          "typ": null,
          "max": 2.5,
          "conditions": "",
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        },
        {
          "name": "Operating ambient temperature",
          "symbol": "TOP",
          "kind": "absolute_maximum",
          "unit": "°C",
          "min": -40,
          "typ": null,
          "max": 85,
          "conditions": "",
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        },
        {
          "name": "Junction temperature",
          "symbol": "TJ",
          "kind": "absolute_maximum",
          "unit": "°C",
          "min": -40,
          "typ": null,
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        {
          "name": "Storage temperature",
          "symbol": "Tstg",
          "kind": "absolute_maximum",
          "unit": "°C",
          "min": -60,
          "typ": null,
          "max": 150,
          "conditions": "",
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        },
        {
          "name": "ESD human body model",
          "symbol": "VESD",
          "kind": "absolute_maximum",
          "unit": "V",
          "min": -2000,
          "typ": null,
          "max": 2000,
          "conditions": "Human body model, JEDEC JS-001",
          "source_page": 2,
          "source": "datasheet"
        },
        {
          "name": "ESD charged device model",
          "symbol": "VESD",
          "kind": "absolute_maximum",
          "unit": "V",
          "min": -750,
          "typ": null,
          "max": 750,
          "conditions": "Charged device model, JEDEC JS-001",
          "source_page": 2,
          "source": "datasheet"
        },
        {
          "name": "Operating supply voltage range",
          "symbol": "VM",
          "kind": "recommended_operating",
          "unit": "V",
          "min": 8,
          "typ": null,
          "max": 45,
          "conditions": "All VM pins connected to the same supply",
          "source_page": 4,
          "source": "datasheet"
        },
        {
          "name": "Reference input voltage",
          "symbol": "VVREF",
          "kind": "recommended_operating",
          "unit": "V",
          "min": 1,
          "typ": null,
          "max": 3.5,
          "conditions": "",
          "source_page": 4,
          "source": "datasheet"
        },
        {
          "name": "V3P3OUT load capability",
          "symbol": "IV3P3",
          "kind": "recommended_operating",
          "unit": "mA",
          "min": null,
          "typ": null,
          "max": 10,
          "conditions": "",
          "source_page": 4,
          "source": "datasheet"
        },
        {
          "name": "Logic operating frequency",
          "symbol": "fPWM",
          "kind": "recommended_operating",
          "unit": "kHz",
          "min": 0,
          "typ": null,
          "max": 100,
          "conditions": "",
          "source_page": 4,
          "source": "datasheet"
        },
        {
          "name": "VM static current",
          "symbol": "IVM",
          "kind": "electrical",
          "unit": "mA",
          "min": null,
          "typ": 2,
          "max": 5,
          "conditions": "VM = 24 V, fPWM < 50 kHz",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "VM sleep current",
          "symbol": "IVMQ",
          "kind": "electrical",
          "unit": "µA",
          "min": null,
          "typ": 1,
          "max": 10,
          "conditions": "VM = 24V",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "VM undervoltage lockout voltage",
          "symbol": "VUVLO",
          "kind": "electrical",
          "unit": "V",
          "min": 6,
          "typ": null,
          "max": 8,
          "conditions": "VM rising",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "V3P3OUT output voltage",
          "symbol": "V3P3",
          "kind": "electrical",
          "unit": "V",
          "min": 3.18,
          "typ": 3.3,
          "max": 3.4,
          "conditions": "IOUT = 0 to 1mA, VM = 24 V, TJ = 25°C",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "V3P3OUT output voltage",
          "symbol": "V3P3",
          "kind": "electrical",
          "unit": "V",
          "min": 3.1,
          "typ": 3.3,
          "max": 3.5,
          "conditions": "IOUT = 0 to 1mA",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "Logic low input voltage",
          "symbol": "VIL",
          "kind": "electrical",
          "unit": "V",
          "min": 0.7,
          "typ": null,
          "max": 0.8,
          "conditions": "",
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          "source": "datasheet"
        },
        {
          "name": "Logic high input voltage",
          "symbol": "VIH",
          "kind": "electrical",
          "unit": "V",
          "min": 1.8,
          "typ": null,
          "max": 5.25,
          "conditions": "",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "Logic low input current",
          "symbol": "IIL",
          "kind": "electrical",
          "unit": "μA",
          "min": -20,
          "typ": null,
          "max": 20,
          "conditions": "VIN = 0V",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "Logic high input current",
          "symbol": "IIH",
          "kind": "electrical",
          "unit": "μA",
          "min": 35,
          "typ": null,
          "max": 50,
          "conditions": "VIN = 3.3V",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "Open-drain output low voltage (nFAULT, nHOME)",
          "symbol": "VOL",
          "kind": "electrical",
          "unit": "V",
          "min": null,
          "typ": null,
          "max": 0.5,
          "conditions": "IO = 5mA",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "Open-drain output high leakage current (nFAULT, nHOME)",
          "symbol": "IOH",
          "kind": "electrical",
          "unit": "μA",
          "min": null,
          "typ": null,
          "max": 1,
          "conditions": "VO = 3.3 V",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "DECAY input low threshold voltage",
          "symbol": "VIL",
          "kind": "electrical",
          "unit": "V",
          "min": 0,
          "typ": null,
          "max": 1.2,
          "conditions": "慢速衰减模式",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "DECAY input high threshold voltage",
          "symbol": "VIH",
          "kind": "electrical",
          "unit": "V",
          "min": 1.8,
          "typ": null,
          "max": null,
          "conditions": "快速衰减模式",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "DECAY input current",
          "symbol": "IDECAY",
          "kind": "electrical",
          "unit": "μA",
          "min": -70,
          "typ": null,
          "max": 70,
          "conditions": "Decay = 5V",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "High-side on-resistance",
          "symbol": "RDS(ON)",
          "kind": "electrical",
          "unit": "Ω",
          "min": null,
          "typ": null,
          "max": 0.2,
          "conditions": "VM = 24 V, IO = 1 A",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "Low-side on-resistance",
          "symbol": "RDS(ON)",
          "kind": "electrical",
          "unit": "Ω",
          "min": null,
          "typ": null,
          "max": 0.2,
          "conditions": "VM = 24 V, IO = 1 A",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "Off-state leakage current",
          "symbol": "IOFF",
          "kind": "electrical",
          "unit": "μA",
          "min": -10,
          "typ": null,
          "max": 10,
          "conditions": "",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "Rise time",
          "symbol": "tR",
          "kind": "timing",
          "unit": "ns",
          "min": 20,
          "typ": null,
          "max": 200,
          "conditions": "VM = 24 V",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "Fall time",
          "symbol": "tF",
          "kind": "timing",
          "unit": "ns",
          "min": 20,
          "typ": null,
          "max": 200,
          "conditions": "VM = 24 V",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "Input anti-glitch time",
          "symbol": "tDEG",
          "kind": "timing",
          "unit": "μs",
          "min": 1.7,
          "typ": null,
          "max": 2.5,
          "conditions": "",
          "source_page": 5,
          "source": "datasheet"
        },
        {
          "name": "xVREF input current",
          "symbol": "IREF",
          "kind": "electrical",
          "unit": "μA",
          "min": -3,
          "typ": null,
          "max": 3,
          "conditions": "xVREF = 3.3 V",
          "source_page": 6,
          "source": "datasheet"
        },
        {
          "name": "xISENSE chopping threshold voltage",
          "symbol": "VTRIP",
          "kind": "electrical",
          "unit": "mV",
          "min": 635,
          "typ": 660,
          "max": 685,
          "conditions": "V(xVREF) = 3.3 V, 100% current ratio",
          "source_page": 6,
          "source": "datasheet"
        },
        {
          "name": "xISENSE chopping accuracy",
          "symbol": "VTRIP",
          "kind": "tolerance",
          "unit": "%",
          "min": -25,
          "typ": null,
          "max": 25,
          "conditions": "xVREF = 3.3V, 5% current ratio",
          "source_page": 6,
          "source": "datasheet"
        },
        {
          "name": "xISENSE chopping accuracy",
          "symbol": "VTRIP",
          "kind": "tolerance",
          "unit": "%",
          "min": -15,
          "typ": null,
          "max": 15,
          "conditions": "xVREF = 3.3V, 10%-34% current ratio",
          "source_page": 6,
          "source": "datasheet"
        },
        {
          "name": "xISENSE chopping accuracy",
          "symbol": "VTRIP",
          "kind": "tolerance",
          "unit": "%",
          "min": -10,
          "typ": null,
          "max": 10,
          "conditions": "xVREF = 3.3V, 38%-67% current ratio",
          "source_page": 6,
          "source": "datasheet"
        },
        {
          "name": "xISENSE chopping accuracy",
          "symbol": "VTRIP",
          "kind": "tolerance",
          "unit": "%",
          "min": -5,
          "typ": null,
          "max": 5,
          "conditions": "xVREF = 3.3V, 71%-100% current ratio",
          "source_page": 6,
          "source": "datasheet"
        },
        {
          "name": "Overcurrent protection level",
          "symbol": "IOCP",
          "kind": "electrical",
          "unit": "A",
          "min": 4,
          "typ": 4.5,
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