LCSC Electronics — Component Search, Datasheets & Ordering

LCSC is JLCPCB's sister company — they share the same parts library and Cxxxxx part numbers. Use LCSC for production sourcing (assembled boards from JLCPCB/PCBWay). DigiKey/Mouser are for prototyping. For BOM management and export workflows, see bom.

Key Differences from DigiKey/Mouser

• No API key needed — jlcsearch community API is free and open
• Lower prices — especially for passives and Chinese-manufactured ICs
• JLCPCB integration — same LCSC part numbers used in JLCPCB assembly BOMs
• Direct PDF downloads — LCSC's CDN (wmsc.lcsc.com) serves datasheets without bot protection
• Low MOQ — many parts available in quantities as low as 1
• Warehouses — Shenzhen (JS), Zhuhai (ZH), Hong Kong (HK)
• Website: https://www.lcsc.com

LCSC Part Numbers

Format: Cxxxxx (e.g., C14663). This is the universal identifier across both LCSC and JLCPCB. Use it for:

• Direct ordering on LCSC
• BOM matching in JLCPCB assembly (see jlcpcb skill)
• Cross-referencing between platforms

jlcsearch API Reference

The jlcsearch community API is the recommended way to search LCSC. No authentication required.

Base URL: https://jlcsearch.tscircuit.com

General Search

GET /api/search?q=<query>&limit=20&full=true

Parameters:

• q — search query (matches MPN, LCSC code, or description keywords)
• package — optional footprint filter (e.g., 0402)
• limit — max results (default 100)
• full — set to true to include all fields (datasheet URL, specs, stock per warehouse)

Category-Specific Search

GET /resistors/list.json?search=10k+0402
GET /capacitors/list.json?search=100nF+0402
GET /microcontrollers/list.json?search=STM32
GET /voltage_regulators/list.json?search=3.3V

Response Format

Results are returned as {"components": [...]}. With full=true, each component has:

{
  "lcsc": 14663,
  "mfr": "GRM155R71C104KA88D",
  "package": "0402",
  "description": "",
  "datasheet": "https://www.lcsc.com/datasheet/...",
  "stock": 2751535,
  "price": [{"qFrom": 1, "qTo": 9, "price": 0.0069}, ...],
  "basic": 0,
  "extra": {
    "number": "C71629",
    "mpn": "GRM155R71C104KA88D",
    "manufacturer": {"id": 4, "name": "Murata Electronics"},
    "package": "0402",
    "description": "16V 100nF X7R ±10% 0402 ...",
    "quantity": 2751535,
    "whs-js": 1234567,
    "whs-zh": 567890,
    "whs-hk": 0,
    "moq": 100,
    "order_multiple": 100,
    "packaging": "Tape & Reel (TR)",
    "packaging_num": 10000,
    "datasheet": {"pdf": "https://wmsc.lcsc.com/wmsc/upload/file/pdf/v2/lcsc/...pdf"},
    "images": [{"96x96": "...", "224x224": "...", "900x900": "..."}],
    "rohs": true,
    "url": "https://www.lcsc.com/product-detail/...",
    "attributes": {
      "Capacitance": "100nF",
      "Voltage Rated": "16V",
      "Temperature Coefficient": "X7R",
      "Tolerance": "±10%"
    },
    "prices": [{"min_qty": 100, "max_qty": 499, "currency": "USD", "price": 0.0048}, ...]
  }
}

Key fields:

• lcsc — numeric LCSC ID (without "C" prefix)
• extra.number — full LCSC code with prefix (e.g., C71629)
• extra.mpn — manufacturer part number
• extra.manufacturer.name — manufacturer
• extra.datasheet.pdf — direct PDF URL (wmsc.lcsc.com CDN, downloads without auth)
• extra.attributes — parametric specs (capacitance, voltage, etc.)
• extra.quantity — total stock across all warehouses
• extra.whs-js, extra.whs-zh, extra.whs-hk — stock per warehouse
• basic — 1 if JLCPCB basic part (no setup fee), 0 if extended
• extra.moq — minimum order quantity
• extra.order_multiple — must order in multiples of this
• extra.rohs — RoHS compliance (boolean)

Rate Limits

The jlcsearch API is community-run with no documented rate limits, but be respectful — use delays of 0.5s between calls.

Datasheet Download & Sync

LCSC's CDN serves datasheet PDFs directly — no bot protection, no special headers needed. This makes LCSC a reliable datasheet source alongside DigiKey.

Datasheet Directory Sync

Use sync_datasheets_lcsc.py to maintain a datasheets/ directory alongside a KiCad project. Same workflow and index.json format as the DigiKey and Mouser skills. No API key required.

# Sync datasheets for a KiCad project
python3 <skill-path>/scripts/sync_datasheets_lcsc.py <file.kicad_sch>

# Preview what would be downloaded
python3 <skill-path>/scripts/sync_datasheets_lcsc.py <file.kicad_sch> --dry-run

# Retry previously failed downloads
python3 <skill-path>/scripts/sync_datasheets_lcsc.py <file.kicad_sch> --force

# Custom output directory
python3 <skill-path>/scripts/sync_datasheets_lcsc.py <file.kicad_sch> -o ./my-datasheets

The script:

• Runs the kicad schematic analyzer to extract components, MPNs, and LCSC codes
• Accepts any identifier — MPN, LCSC code, or other distributor PNs from KiCad symbol properties
• Prefers LCSC code for search (exact match) — falls back to MPN keyword search
• Downloads from LCSC CDN — direct PDF URLs, no bot protection
• Writes index.json manifest — same format as DigiKey/Mouser skills
• Verifies PDF content — checks MPN, manufacturer, and description keywords
• Rate-limited — 0.5s between API calls (configurable with --delay)
• Saves progress incrementally — safe to interrupt

Single Datasheet Download

Use fetch_datasheet_lcsc.py for one-off downloads.

# Search by MPN
python3 <skill-path>/scripts/fetch_datasheet_lcsc.py --search "GRM155R71C104KA88D" -o datasheet.pdf

# Search by LCSC code
python3 <skill-path>/scripts/fetch_datasheet_lcsc.py --search "C14663" -o datasheet.pdf

# Direct URL download
python3 <skill-path>/scripts/fetch_datasheet_lcsc.py "https://wmsc.lcsc.com/..." -o datasheet.pdf

# JSON output
python3 <skill-path>/scripts/fetch_datasheet_lcsc.py --search "C14663" --json

The script:

• OS-agnostic — uses requests → urllib → playwright fallback chain (no wget/curl)
• Validates PDF headers — rejects HTML error pages
• Falls back to alternative manufacturer sources when LCSC URL fails
• Exit codes: 0 = success, 1 = download failed, 2 = search/API error
• Dependencies:
  • pip install requests (recommended; urllib fallback works fine for LCSC)
  • pip install playwright && playwright install chromium (optional; rarely needed for LCSC)

LCSC Official API (Requires Approval)

Base URL: https://ips.lcsc.com. Requires API key + signature authentication. Contact support@lcsc.com for access. Rarely needed — jlcsearch covers most use cases.

Web Search Fallback

If the jlcsearch API is unavailable, search LCSC via WebFetch:

https://www.lcsc.com/search?q=<query>

Cross-Referencing & Missing Equivalents

LCSC part numbers are specific to the LCSC/JLCPCB ecosystem. Use the extra.mpn field to cross-reference on DigiKey/Mouser.

When an MPN has no exact LCSC match:

1. Search by key parameters (e.g., "100nF 0402 X7R 16V")
2. Look for pin-compatible alternatives from Chinese manufacturers
3. Verify specs and footprint match — pad dimensions can vary even within the same package size
4. As a last resort, mark as "consigned" and source separately

Tips

• basic field matters — JLCPCB basic parts have no setup fee; extended parts cost $3 each
• Check stock per warehouse (whs-js, whs-zh, whs-hk) — availability varies
• moq and order_multiple — many parts require minimum quantities or specific multiples
• Datasheet quality varies for Chinese manufacturers — cross-reference MPN on DigiKey for better docs

Platform Guidance

• Claude Code: Present part search results as tables. Use AskUserQuestion to confirm part selection before adding to BOM.
• Codex/OpenCode: Present results as numbered options. Ask user to type selection number.
• CLI: All part search and sourcing operations available via circuit-weaver subcommands.