AT9880B

{
  "slug": "at9880b",
  "version": "0.1.0",
  "type": "component",
  "description": "ZHONGKEWEI GNSS Modules, QFN-40L-EP(5x5). Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",
  "tags": [
    "component",
    "iot-communication modules",
    "at9880b",
    "factory-2.0.0",
    "extractor-text"
  ],
  "dependencies": {},
  "hero": {
    "type": "image",
    "path": "docs/hero.png"
  },
  "files": [
    "page.json",
    "README.md",
    "at9880b.kicad_sym",
    "at9880b.kicad_mod",
    "at9880b.glb",
    "at9880b.step",
    "at9880b.lbr",
    "docs/hero.png",
    "docs/at9880b-datasheet.pdf",
    "viewers/symbol.html",
    "viewers/footprint.html",
    "at9880b-hero.glb",
    "at9880b-hero.overlay.json",
    "at9880b-etched.glb"
  ],
  "component": {
    "mpn": "AT9880B",
    "manufacturer": "ZHONGKEWEI",
    "package": "QFN-40L-EP(5x5)",
    "pin_count": 41,
    "category": "IoT/Communication Modules",
    "subcategory": "GNSS Modules",
    "datasheet": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8604434706083827712",
    "parts": {
      "symbol": "at9880b.kicad_sym",
      "footprint": "at9880b.kicad_mod",
      "model_3d": "at9880b-hero.glb",
      "model_3d_plain": "at9880b-etched.glb",
      "model_3d_step": "at9880b-etched.step",
      "model_3d_step_plain": "at9880b.step",
      "lbr": "at9880b.lbr"
    },
    "distributor_links": {
      "lcsc": "C42371070"
    },
    "distributor_check": {
      "checked_at": "2026-10-18T13:54:59Z",
      "source": "Component Ocean /api/assign-pns",
      "digikey": {
        "pn": null,
        "status": "quota"
      },
      "mouser": {
        "pn": null,
        "status": "quota"
      }
    },
    "pins": [
      {
        "number": "1",
        "name": "RF1",
        "type": "input",
        "description": "L1 band RF signal input; DC voltage on this pin must not exceed 0.8V, so a DC-blocking capacitor is needed if the external LNA output carries DC."
      },
      {
        "number": "2",
        "name": "GND",
        "type": "power_in",
        "description": "Ground; connect to GND and use as part of the RF input isolation ground next to RF1."
      },
      {
        "number": "3",
        "name": "VDD_ANA",
        "type": "power_out",
        "description": "Analog LDO output; connect a 1uF decoupling capacitor."
      },
      {
        "number": "4",
        "name": "VX_OUT",
        "type": "power_out",
        "description": "Supply output for the external TCXO, typically 1.8V; connect a 1uF decoupling capacitor."
      },
      {
        "number": "5",
        "name": "XREF",
        "type": "input",
        "description": "Reference clock input for an external TCXO (26 MHz, clipped sine, 0.5-1.5 Vpp)."
      },
      {
        "number": "6",
        "name": "TST_RF",
        "type": "passive",
        "description": "RF test port; leave unconnected when not used."
      },
      {
        "number": "7",
        "name": "VDD_BK",
        "type": "power_out",
        "description": "Backup LDO output; a decoupling capacitor must be connected to this pin whether or not a backup supply is fitted."
      },
      {
        "number": "8",
        "name": "VBAT",
        "type": "power_in",
        "description": "Backup power input for RTC and backup RAM, operating range 1.4-3.6V; may be left floating if no hot-start backup is needed."
      },
      {
        "number": "9",
        "name": "VDD_IO",
        "type": "power_in",
        "description": "Digital I/O supply input, 2.7-3.6V (3.3V typical), also powering the power-on reset and antenna detect circuits."
      },
      {
        "number": "10",
        "name": "ANT_BIAS",
        "type": "bidirectional",
        "description": "Active antenna bias output and detection; detection supply is VDD_IO up to 3.6V, with short-circuit protection limiting current to about 45-65 mA."
      },
      {
        "number": "11",
        "name": "RTC_O",
        "type": "passive",
        "description": "RTC 32.768 kHz oscillator output for a passive crystal connected between RTC_I and RTC_O."
      },
      {
        "number": "12",
        "name": "RTC_I",
        "type": "passive",
        "description": "RTC 32.768 kHz oscillator input for a passive crystal connected between RTC_I and RTC_O."
      },
      {
        "number": "13",
        "name": "GPIO2/TXD1",
        "type": "bidirectional",
        "description": "General-purpose I/O multiplexed as UART1 transmit (TXD1)."
      },
      {
        "number": "14",
        "name": "GPIO3/RXD1",
        "type": "bidirectional",
        "description": "General-purpose I/O multiplexed as UART1 receive (RXD1)."
      },
      {
        "number": "15",
        "name": "Reserved",
        "type": "bidirectional",
        "description": "Reserved digital pin; leave unconnected when not used."
      },
      {
        "number": "16",
        "name": "Reserved",
        "type": "bidirectional",
        "description": "Reserved digital pin; leave unconnected when not used."
      },
      {
        "number": "17",
        "name": "nRST",
        "type": "input",
        "description": "External active reset input with internal pull-up; leave unconnected when not used."
      },
      {
        "number": "18",
        "name": "GPIO1/RXD0",
        "type": "bidirectional",
        "description": "General-purpose I/O multiplexed as UART0 receive (RXD0), the default navigation data interface."
      },
      {
        "number": "19",
        "name": "GPIO0/TXD0",
        "type": "bidirectional",
        "description": "General-purpose I/O multiplexed as UART0 transmit (TXD0), the default navigation data output."
      },
      {
        "number": "20",
        "name": "GPIO27",
        "type": "bidirectional",
        "description": "General-purpose I/O."
      },
      {
        "number": "21",
        "name": "DX_IN",
        "type": "power_in",
        "description": "Internal DCDC input, 2.7-3.6V; place at least 2.2uF filter capacitance close to this pin."
      },
      {
        "number": "22",
        "name": "DX_OUT",
        "type": "passive",
        "description": "Internal DCDC output; requires a 4.7uH inductor and at least 10uF output capacitor (recommended 4.7uH + 10uF), or left floating when an external core supply is used."
      },
      {
        "number": "23",
        "name": "VCORE",
        "type": "power_in",
        "description": "Core LDO input, 1.2-3.6V; can be powered directly by an external supply."
      },
      {
        "number": "24",
        "name": "VDD_BB",
        "type": "power_out",
        "description": "Digital core LDO output; connect a 2.2uF decoupling capacitor."
      },
      {
        "number": "25",
        "name": "GPIO22",
        "type": "bidirectional",
        "description": "General-purpose I/O, default function is 1PPS output."
      },
      {
        "number": "26",
        "name": "Reserved",
        "type": "bidirectional",
        "description": "Reserved digital pin; leave unconnected when not used."
      },
      {
        "number": "27",
        "name": "Reserved",
        "type": "bidirectional",
        "description": "Reserved digital pin; leave unconnected when not used."
      },
      {
        "number": "28",
        "name": "Reserved",
        "type": "bidirectional",
        "description": "Test port; leave unconnected when not used."
      },
      {
        "number": "29",
        "name": "ON_OFF",
        "type": "input",
        "description": "Shutdown control with internal pull-up; driving low puts the chip into sleep mode and high resumes full operation; leave unconnected when not used."
      },
      {
        "number": "30",
        "name": "GPIO4",
        "type": "bidirectional",
        "description": "General-purpose I/O; leave unconnected when not used."
      },
      {
        "number": "31",
        "name": "GPIO5",
        "type": "bidirectional",
        "description": "General-purpose I/O; leave unconnected when not used."
      },
      {
        "number": "32",
        "name": "GPIO8",
        "type": "bidirectional",
        "description": "General-purpose I/O; leave unconnected when not used."
      },
      {
        "number": "33",
        "name": "GPIO7",
        "type": "bidirectional",
        "description": "General-purpose I/O; leave unconnected when not used."
      },
      {
        "number": "34",
        "name": "GPIO6",
        "type": "bidirectional",
        "description": "General-purpose I/O; leave unconnected when not used."
      },
      {
        "number": "35",
        "name": "GPIO10",
        "type": "bidirectional",
        "description": "General-purpose I/O; leave unconnected when not used."
      },
      {
        "number": "36",
        "name": "GPIO9",
        "type": "bidirectional",
        "description": "General-purpose I/O; leave unconnected when not used."
      },
      {
        "number": "37",
        "name": "DVDD",
        "type": "passive",
        "description": "PLL LDO output; connect a 1uF decoupling capacitor."
      },
      {
        "number": "38",
        "name": "GND",
        "type": "power_in",
        "description": "Ground; connect to GND and use as part of the RF input isolation ground next to RF2."
      },
      {
        "number": "39",
        "name": "RF2",
        "type": "input",
        "description": "L5 band RF signal input; DC voltage on this pin must not exceed 0.8V, so a DC-blocking capacitor is needed if the external LNA output carries DC."
      },
      {
        "number": "40",
        "name": "GND",
        "type": "power_in",
        "description": "Ground; connect to GND."
      },
      {
        "number": "41",
        "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: The datasheet pinout table (section 2.2) gives only the pin names, I/O categories and functions; the; KiCad types for analog/digital IO pins are my mapping of the datasheet's categories: 'digital bidire; Pins 15, 16, 26, 27 and 28 are labelled 'Reserved' in the table; the datasheet says leave unused res",
          "exposed pad 41 added from the footprint",
          "dropped thermal pad ['EP'] absent from footprint",
          "5/41 pins cited to the wrong page (name found elsewhere): ['15:Reserved@p3', '16:Reserved@p3', '26:Reserved@p3', '27:Reserved@p3']"
        ],
        "pages_sent": 16,
        "cost_usd": 0.0767,
        "at": "2026-10-18T13:54:36"
      },
      "datasheet": {
        "url": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8604434706083827712",
        "pages": 16,
        "sha256": "5fe9aedab37df3ec",
        "source_tier": "lcsc"
      },
      "cad": "KiCad official (CC-BY-SA 4.0)",
      "pins": {
        "total": 41,
        "described": 41,
        "cites_pages": true,
        "refuses_to_fabricate": true
      }
    },
    "viewers": {
      "symbol": "viewers/symbol.html",
      "footprint": "viewers/footprint.html"
    },
    "models_3d": [
      {
        "file": "at9880b.step",
        "role": "plain",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "z = 0",
        "extents_mm": [
          5.0,
          5.0,
          0.77
        ],
        "zmin_mm": 0.0,
        "centre_offset_mm": 0.0,
        "footprint_binding": "identity",
        "sha256": "8f37bc7a9aab4742c34f137d9822c0352acc227532830034555744338483cdfc",
        "checked": "2026-10-18",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      },
      {
        "file": "at9880b-etched.step",
        "role": "eda",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "z = 0",
        "extents_mm": [
          5.0,
          5.0,
          0.77
        ],
        "zmin_mm": 0.0,
        "centre_offset_mm": 0.0,
        "footprint_binding": "identity",
        "sha256": "c6bbed152d2dbbbd64a844826a152d1d0b0312f08356477b31e64e6a5acbab5d",
        "checked": "2026-10-18",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      }
    ]
  }
}