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
8. Recommendations for Certification
This section provides additional information on the certification details already provided in the WFM200 data sheet.
WFM200 embeds TX power backoffs for 2:1 VSWR on its RF ports and is certified with an external connectorized coaxial dipole anten-
na and an integrated module antenna.
Except for minor cosmetic changes, most changes to an FCC certified equipment require testing to determine whether the change is a
Class I or Class II permissive change.
For more details about using the Single Modular Transmitter, such as WFM200, refer to the following FCC documents:
• KDB 996369 D01 Transmitter Module Equipment Authorization Guide
• KDB 996369 D02 Frequently Asked Questions and Answers about Modules
• KDB 178919 D01 Permissive Change Policy
• KDB 178919 D02 Permissive Change Frequently-Asked Questions
Certification was performed with:
• Linux driver 2.2.4
• WLAN firmware FW3.0.1
8.1 Qualified External Antenna Type
The WFM200 SiP module has been certified in multiple regions and is designed to operate with a connectorized whip dipole antenna
type with a reference impedance of 50 Ω. FCC certification is restricted to external antennas of this type. The maximum antenna gain is
+4.7 dBi. System integrators must comply with all regulatory agency requirements for the applicable regions including FCC, IC, and CE,
especially those governing antennas used with this module.
Table 8.1. Certified and Approved External Antennas and Board Sizes
External Antenna Type
Specification for max.
VSWR
Specified Max. Gain [dBi] Notes
Connectorized Whip Dipole 2:1 +4.7
Straight or 90 degrees bent W1038 anten-
na, or similar type
UG395: WFM200 Hardware Design User's Guide
Recommendations for Certification
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