User's Guide
Table Of Contents
- 1. WFM200 Pinout
- 2. Device Configuration
- 3. Features Description
- 4. Power Supplies
- 5. Application Schematic Recommendations
- 6. Typical Application Schematics
- 7. Layout Recommendations
- 7.1 Generic RF Layout Considerations
- 7.2 GND and RF Pads Including the Diversity Port and External Antennas
- 7.3 Module Antenna
- 7.3.1 Small Board Size Recommendations for Good RF Performance
- 7.3.2 Extended X Dimension Recommendation for Good RF Performance
- 7.3.3 Y Dimension (65 to 80 mm) Recommendation for Good RF Performance
- 7.3.4 Y Dimension (80 mm or Larger) Recommendation for Good RF Performance
- 7.3.5 WFM200 Portion One Corner Bias with 3 mm Metal Keep-Outs
- 7.3.6 Recommended Antenna Loop Trace Capacitor Values
- 7.4 WFM200 Reference Evaluation Board
- 8. Recommendations for Certification
- 9. Package Outline
- 10. Integral Antenna Loop and Keep-Out Required Dimensions
- 11. Recommended PCB Land Pattern
7.3.3 Y Dimension (65 to 80 mm) Recommendation for Good RF Performance
Figure 7.6. Reference Design for Extended X- and Slightly Extended Y-dimensioned PCB Sizes*
Note: Spaces filled in black represent metal keep-outs on the PCB in the figure above.*
• Add 3 mm wide keep-outs adjacent to the designated Component Placement Areas near the WFM200, which allows only an 18 mm
wide bridge of GND and signal routing area between the two PCB portions.
• The 20.5 mm corners beyond the placement areas must be metal keep-outs.
• PCB may be slightly larger to account for PCB edge routing.
• Main portion of the PCB X dimension can be any length.
• Main portion of PCB Y dimension can be any length over 65 mm.
• WF(M)200S portion of board X dimension is 17.5 mm +/-3 mm.
• WF(M)200S portion of board Y dimension is 45 mm to 55 mm.
• Pins 49 and 48 are to be centered vertically, and center of Pin 49 is 1.8 mm from metal edge.
• Connectors are only allowed in the Extension X dimension portion away from WFM200.
• Components may be placed north and south of the occupied area, but only within the designated component placement areas. Also,
these must be surrounded by GND to the edge of the placement areas.
UG395: WFM200 Hardware Design User's Guide
Layout Recommendations
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