CH344Q

{
  "slug": "ch344q",
  "version": "0.1.0",
  "type": "component",
  "description": "WCH Jiangsu Qin Heng USB Converters, LQFP-48(7x7). Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",
  "tags": [
    "component",
    "interface",
    "ch344q",
    "factory-2.0.0",
    "extractor-text"
  ],
  "dependencies": {},
  "hero": {
    "type": "image",
    "path": "docs/hero.png"
  },
  "files": [
    "page.json",
    "README.md",
    "ch344q.kicad_sym",
    "ch344q.kicad_mod",
    "ch344q.glb",
    "ch344q.step",
    "ch344q.lbr",
    "docs/hero.png",
    "docs/ch344q-datasheet.pdf",
    "viewers/symbol.html",
    "viewers/footprint.html",
    "ch344q-hero.glb",
    "ch344q-hero.overlay.json",
    "ch344q-etched.glb"
  ],
  "component": {
    "mpn": "CH344Q",
    "manufacturer": "WCH Jiangsu Qin Heng",
    "package": "LQFP-48(7x7)",
    "pin_count": 48,
    "category": "Interface",
    "subcategory": "USB Converters",
    "datasheet": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8618866915339493376",
    "parts": {
      "symbol": "ch344q.kicad_sym",
      "footprint": "ch344q.kicad_mod",
      "model_3d": "ch344q-hero.glb",
      "model_3d_plain": "ch344q-etched.glb",
      "model_3d_step": "ch344q-etched.step",
      "model_3d_step_plain": "ch344q.step",
      "lbr": "ch344q.lbr"
    },
    "distributor_links": {
      "lcsc": "C2988084"
    },
    "distributor_check": {
      "checked_at": "2026-10-18T08:59:29Z",
      "source": "Component Ocean /api/assign-pns",
      "digikey": {
        "pn": null,
        "status": "quota"
      },
      "mouser": {
        "pn": null,
        "status": "quota"
      }
    },
    "pins": [
      {
        "number": "1",
        "name": "NC",
        "type": "unconnected",
        "description": "No internal connection; must be left floating (禁止连接，必须悬空)."
      },
      {
        "number": "2",
        "name": "DSR2",
        "type": "input",
        "description": "UART2 modem input, data set ready, active low."
      },
      {
        "number": "3",
        "name": "RI2",
        "type": "input",
        "description": "UART2 modem input, ring indicator, active low."
      },
      {
        "number": "4",
        "name": "DCD2",
        "type": "input",
        "description": "UART2 modem input, carrier detect, active low."
      },
      {
        "number": "5",
        "name": "XI",
        "type": "input",
        "description": "Crystal oscillator input; 8MHz crystal between XI and XO with about 22pF load capacitors to GND."
      },
      {
        "number": "6",
        "name": "XO",
        "type": "output",
        "description": "Crystal oscillator inverting output; 8MHz crystal between XI and XO with about 22pF load capacitor to GND."
      },
      {
        "number": "7",
        "name": "RESET",
        "type": "input",
        "description": "External reset input, active low, with internal pull-up (typical 30 ms reset delay after power-up or reset input)."
      },
      {
        "number": "8",
        "name": "GND",
        "type": "power_in",
        "description": "Common ground; must be connected to the USB bus ground."
      },
      {
        "number": "9",
        "name": "VCC",
        "type": "power_in",
        "description": "Positive supply input, 3.0 V to 3.6 V (3.3 V typical); needs external 0.1uF decoupling capacitor."
      },
      {
        "number": "10",
        "name": "CTS1/GPIO2",
        "type": "bidirectional",
        "description": "UART1 modem input, clear to send, active low; also general-purpose GPIO2."
      },
      {
        "number": "11",
        "name": "RTS1/GPIO3",
        "type": "bidirectional",
        "description": "UART1 modem output, request to send, active low; also general-purpose GPIO3."
      },
      {
        "number": "12",
        "name": "TXD1",
        "type": "output",
        "description": "UART1 serial data output; idle state high."
      },
      {
        "number": "13",
        "name": "RXD1",
        "type": "input",
        "description": "UART1 serial data input with internal pull-up."
      },
      {
        "number": "14",
        "name": "ACT/CFG/DCD3",
        "type": "output",
        "description": "USB configured status output, active low, also hardware flow-control enable with internal pull-up; when RTS3 is strapped low at power-up it becomes the UART3 DCD3 carrier-detect input, active low."
      },
      {
        "number": "15",
        "name": "TX_S/RI3",
        "type": "output",
        "description": "Serial transmit status output (200 ms pulse while any UART is sending); when RTS3 is strapped low at power-up it becomes the UART3 RI3 ring-indicator input, active low."
      },
      {
        "number": "16",
        "name": "RX_S/DSR3",
        "type": "output",
        "description": "Serial receive status output (200 ms pulse while any UART is receiving); when RTS3 is strapped low at power-up it becomes the UART3 DSR3 data-set-ready input, active low."
      },
      {
        "number": "17",
        "name": "DSR1",
        "type": "input",
        "description": "UART1 modem input, data set ready, active low."
      },
      {
        "number": "18",
        "name": "DTR1/TNOW1/GPIO9",
        "type": "bidirectional",
        "description": "UART1 modem output DTR, active low, or RS485 TNOW1 direction control per power-up strap (pull-down selects TNOW); also general-purpose GPIO9."
      },
      {
        "number": "19",
        "name": "DTR2/TNOW2/GPIO10",
        "type": "bidirectional",
        "description": "UART2 modem output DTR, active low, or RS485 TNOW2 direction control per power-up strap (pull-down selects TNOW); also general-purpose GPIO10."
      },
      {
        "number": "20",
        "name": "GND",
        "type": "power_in",
        "description": "Common ground; must be connected to the USB bus ground."
      },
      {
        "number": "21",
        "name": "TXD2",
        "type": "output",
        "description": "UART2 serial data output; idle state high."
      },
      {
        "number": "22",
        "name": "RXD2",
        "type": "input",
        "description": "UART2 serial data input with internal pull-up; input is 5V tolerant (FT)."
      },
      {
        "number": "23",
        "name": "GND",
        "type": "power_in",
        "description": "Common ground; must be connected to the USB bus ground."
      },
      {
        "number": "24",
        "name": "VCC",
        "type": "power_in",
        "description": "Positive supply input, 3.0 V to 3.6 V (3.3 V typical); needs external 0.1uF decoupling capacitor."
      },
      {
        "number": "25",
        "name": "RI1",
        "type": "input",
        "description": "UART1 modem input, ring indicator, active low; input is 5V tolerant (FT)."
      },
      {
        "number": "26",
        "name": "CTS2/GPIO4",
        "type": "bidirectional",
        "description": "UART2 modem input, clear to send, active low; also general-purpose GPIO4."
      },
      {
        "number": "27",
        "name": "RTS2/GPIO5",
        "type": "bidirectional",
        "description": "UART2 modem output, request to send, active low; also general-purpose GPIO5."
      },
      {
        "number": "28",
        "name": "DCD1/GPIO15",
        "type": "bidirectional",
        "description": "UART1 modem input, carrier detect, active low; input is 5V tolerant (FT); also general-purpose GPIO15."
      },
      {
        "number": "29",
        "name": "DSR0/GPIO14",
        "type": "bidirectional",
        "description": "UART0 modem input, data set ready, active low; input is 5V tolerant (FT); also general-purpose GPIO14."
      },
      {
        "number": "30",
        "name": "TXD0",
        "type": "output",
        "description": "UART0 serial data output; idle state high."
      },
      {
        "number": "31",
        "name": "RXD0",
        "type": "input",
        "description": "UART0 serial data input with internal pull-up; input is 5V tolerant (FT)."
      },
      {
        "number": "32",
        "name": "RI0/GPIO13",
        "type": "bidirectional",
        "description": "UART0 modem input, ring indicator, active low; input is 5V tolerant (FT); also general-purpose GPIO13."
      },
      {
        "number": "33",
        "name": "DCD0/GPIO12",
        "type": "bidirectional",
        "description": "UART0 modem input, carrier detect, active low; input is 5V tolerant (FT); also general-purpose GPIO12."
      },
      {
        "number": "34",
        "name": "DTR3/TNOW3/GPIO11",
        "type": "bidirectional",
        "description": "UART3 modem output DTR, active low, or RS485 TNOW3 direction control per power-up strap (pull-down selects TNOW); input is 5V tolerant (FT); also general-purpose GPIO11."
      },
      {
        "number": "35",
        "name": "GND",
        "type": "power_in",
        "description": "Common ground; must be connected to the USB bus ground."
      },
      {
        "number": "36",
        "name": "VCC",
        "type": "power_in",
        "description": "Positive supply input, 3.0 V to 3.6 V (3.3 V typical); needs external 0.1uF decoupling capacitor."
      },
      {
        "number": "37",
        "name": "TXD3",
        "type": "output",
        "description": "UART3 serial data output; idle state high."
      },
      {
        "number": "38",
        "name": "RXD3",
        "type": "input",
        "description": "UART3 serial data input; requires an external pull-up resistor (no internal pull-up); input is 5V tolerant (FT)."
      },
      {
        "number": "39",
        "name": "DTR0/TNOW0/GPIO8",
        "type": "bidirectional",
        "description": "UART0 modem output DTR, active low, or RS485 TNOW0 direction control per power-up strap (pull-down selects TNOW); input is 5V tolerant (FT); also general-purpose GPIO8."
      },
      {
        "number": "40",
        "name": "RTS0/GPIO1",
        "type": "bidirectional",
        "description": "UART0 modem output, request to send, active low; a pull-down at power-up disables EEPROM parameters and enables built-in defaults; also general-purpose GPIO1."
      },
      {
        "number": "41",
        "name": "CTS0/GPIO0",
        "type": "bidirectional",
        "description": "UART0 modem input, clear to send, active low; input is 5V tolerant (FT); also general-purpose GPIO0."
      },
      {
        "number": "42",
        "name": "UD-",
        "type": "bidirectional",
        "description": "USB D- data line connected directly to the USB bus; no series resistor allowed."
      },
      {
        "number": "43",
        "name": "UD+",
        "type": "bidirectional",
        "description": "USB D+ data line connected directly to the USB bus; no series resistor allowed."
      },
      {
        "number": "44",
        "name": "TEST",
        "type": "input",
        "description": "Internal test pin; connect to GND through a pull-down resistor (typically 4.7 kΩ) or tie directly to GND."
      },
      {
        "number": "45",
        "name": "RTS3/GPIO7",
        "type": "bidirectional",
        "description": "UART3 modem output, request to send, active low; a pull-down at power-up enables DCD3/RI3/DSR3 on pins 14/15/16; also general-purpose GPIO7."
      },
      {
        "number": "46",
        "name": "CTS3/GPIO6",
        "type": "bidirectional",
        "description": "UART3 modem input, clear to send, active low; input is 5V tolerant (FT); also general-purpose GPIO6."
      },
      {
        "number": "47",
        "name": "GND",
        "type": "power_in",
        "description": "Common ground; must be connected to the USB bus ground."
      },
      {
        "number": "48",
        "name": "VCC",
        "type": "power_in",
        "description": "Positive supply input, 3.0 V to 3.6 V (3.3 V typical); needs external 0.1uF decoupling capacitor."
      }
    ],
    "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 pin table lists pin 14 as output (ACT). It is typed output here, but it doubles as the; Several pins have power-up strap-selected alternate functions (ACT/CFG/DCD3, TX_S/RI3, RX_S/DSR3, DT; The CH344 manual covers both CH344Q and CH344L in one table. Only the CH344Q column was used. CFG (C",
          "1/48 pins cited to the wrong page (name found elsewhere): ['5:XI@p3']",
          "1/48 pin names appear NOWHERE in the datasheet text: ['6:XO@p3']"
        ],
        "pages_sent": 8,
        "cost_usd": 0.0993,
        "at": "2026-10-18T08:58:19"
      },
      "datasheet": {
        "url": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8618866915339493376",
        "pages": 8,
        "sha256": "9044ddf347f308c1",
        "source_tier": "lcsc"
      },
      "cad": "KiCad official (CC-BY-SA 4.0)",
      "pins": {
        "total": 48,
        "described": 48,
        "cites_pages": true,
        "refuses_to_fabricate": true
      }
    },
    "viewers": {
      "symbol": "viewers/symbol.html",
      "footprint": "viewers/footprint.html"
    },
    "models_3d": [
      {
        "file": "ch344q.step",
        "role": "plain",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "z = 0",
        "extents_mm": [
          9.0,
          9.0,
          1.5
        ],
        "zmin_mm": -0.0,
        "centre_offset_mm": 0.0,
        "footprint_binding": "identity",
        "sha256": "9dea352d93177c2904afd7d7b68ea8855ce1ab691f69f8b3e13655600514b6bf",
        "checked": "2026-10-18",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      },
      {
        "file": "ch344q-etched.step",
        "role": "eda",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "z = 0",
        "extents_mm": [
          9.0,
          9.0,
          1.5
        ],
        "zmin_mm": -0.0,
        "centre_offset_mm": 0.0,
        "footprint_binding": "identity",
        "sha256": "3e08889b74eebaec307561646e9639622ab36f0924041f5d9584268fcc96cb86",
        "checked": "2026-10-18",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      }
    ]
  }
}