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
7.3.4 Y Dimension (80 mm or Larger) Recommendation for Good RF Performance
Figure 7.7. Reference Design for Extended X- and Y-dimensioned PCB Sizes*
Note: Spaces filled in black represent metal keep-outs on the PCB in the figure above.*
• WFM200 PCB portion size is X = 17.5 mm and Y= 45 mm of metal.
• PCB may be slightly larger to account for PCB edge routing.
• Main portion of PCB X dimension can be any length.
• The Y dimension of PCB may be of any length, however, 3 mm metal keep-outs must be placed as shown. There must only be an
18 mm x 3 mm area where traces and GND fill can bridge between the two portions of the PCB.
• Pins 49 and 48 are to be centered vertically, and the center of pin 49 is 1.8 mm from metal edge.
• Connectors are allowed in the extension X dimension portion away from WFM200.
• If connectors are placed in the 17.5 mm corners north or south of the designated component placement areas, testing must be per-
formed with cables in place to assure good RF performance.
• Components may be placed in the component placement areas, and north and south of these areas beyond the 3 mm metal keep-
out gap.
• Component placement areas must have GND surrounding them to the edge of the placement areas.
UG395: WFM200 Hardware Design User's Guide
Layout Recommendations
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