• XINGLIGHT product page: https://www.xinglight.cn/index.php?c=show&id=3499
• XINGLIGHT product-page PDF link: https://www.xinglight.cn/uploadfile/202512/1681d33d865e1f4.pdf
• Search-discovered direct PDF mirror/reference: https://datasheet5.oss-cn-shanghai.aliyuncs.com/datasheets/xinglight/XL-3528RGBW-WS2812B.pdf
• LCSC PDF mirror: https://datasheet.lcsc.com/lcsc/2307071349_XINGLIGHT-XL-3528RGBW-WS2812B_C2890364.pdf

• Pin numbers match the datasheet: 1 GND, 2 DI, 3 VDD, 4 DO.
• Symbol physical placement matches the datasheet orientation: GND lower-right, DI upper-right, VDD upper-left, DO lower-left.
• All four terminal Pin Type values are currently Unspecified.
• No explicit Pin Description values were found on the terminals, even though the datasheet provides clear descriptions.

• Pad size: 0.90 mm × 0.75 mm
• Vertical pitch between same-side pads: 1.50 mm
• Horizontal inner-edge spacing between left and right pad groups: 1.80 mm

Kicad
pad 1 smd rect (at 1.350 0.75 90)  (size 0.750 0.900)
pad 2 smd rect (at 1.350 -0.75 90) (size 0.750 0.900)
pad 3 smd rect (at -1.350 -0.75 90) (size 0.750 0.900)
pad 4 smd rect (at -1.350 0.75 90)  (size 0.750 0.900)

• Fab outline: ±1.75 mm × ±1.40 mm → 3.50 mm × 2.80 mm, matching the datasheet body size.
• Courtyard: ±2.80 mm × ±2.40 mm → 5.60 mm × 4.80 mm; this is larger than the body as expected and not a mismatch by itself.
• Silk includes a pin-1/orientation marker near the right side; Flux/KiCad Y-axis conversion should be kept in mind when comparing raw coordinates to rendered board view.

• Recommended solder pads match the datasheet.
• Pin/pad numbering and side placement match the schematic and datasheet.
• The computed footprint packageSize is 0 × 0 × 0, which is incomplete metadata even though the fab outline and 3D model exist.

1. Project description/package text mismatch
   Current project description context says SMD,1.8x2mm ... 3720, while the official XINGLIGHT datasheet says SMD3528-4P / 3.50 × 2.80 × 1.85 mm. This is the largest metadata mismatch.
2. Package / case metadata missing
   No explicit Package or Case Code property was found. Suggested value: SMD3528-4P or 1411 (3528 Metric), depending on the preferred library convention.
3. Pin types are unspecified
   All four terminals currently have Pin Type: Unspecified. For better ERC behavior, set GND/VDD as power-related, DI as input, and DO as output.
4. Pin descriptions missing
   Datasheet pin descriptions are not populated in the terminal properties. Suggested descriptions are listed in the pin cross-check table above.
5. Computed package size metadata is incomplete
   Footprint computed packageSize is 0 × 0 × 0 despite the datasheet body being 3.50 × 2.80 × 1.85 mm.
6. RGBW naming ambiguity
   The MPN contains RGBW, but the extracted datasheet content describes a 24-bit GRB data stream and lists optical/electrical parameters for R/G/B only. If this part is expected to provide a separate white channel, that is not supported by the extracted datasheet text and should be verified visually in the official PDF.
7. Operating-temperature ambiguity
   Source extraction surfaced both −40 to +85 °C and −20 to +85 °C depending on section/source. Use the original PDF table as authoritative before advertising a final temperature rating.