Product Info
Table Of Contents
- About the Document
- Contents
- Table Index
- Figure Index
- 1 Introduction
- 2 Product Concept
- 3 Application Interfaces
- 3.1. General Description
- 3.2. Pin Assignment
- 3.3. Pin Description
- 3.4. Power Supply
- 3.5. Turn on and off Scenarios
- 3.6. VRTC Interface
- 3.7. Power Output
- 3.8. Battery Charge and Management
- 3.9. USB Interfaces
- 3.10. UART Interfaces
- 3.11. (U)SIM Interfaces
- 3.12. SD Card Interface
- 3.13. GPIO Interfaces
- 3.14. I2C Interfaces
- 3.15. I2S Interfaces
- 3.16. SPI Interface
- 3.17. ADC Interfaces
- 3.18. LCM Interfaces
- 3.19. Touch Panel Interfaces
- 3.20. Camera Interfaces
- 3.21. Sensor Interfaces
- 3.22. Audio Interfaces
- 3.23. Emergency Download Interface
- 4 Wi-Fi and BT
- 5 GNSS
- 6 Antenna Interfaces
- 7 Electrical, Reliability and Radio Characteristics
- 8 Mechanical Dimensions
- 9 Storage, Manufacturing and Packaging
- 10 Appendix A References
- 11 Appendix B GPRS Coding Schemes
- 12 Appendix C GPRS Multi-slot Classes
- 13 Appendix D EDGE Modulation and Coding Schemes
- IC & FCC Requirement
Smart LTE Module Series
SC66 Hardware Design
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5.2. GNSS RF Design Guidelines
Bad design of antenna and layout may cause reduced GNSS receiving sensitivity, longer GNSS
positioning time, or reduced positioning accuracy. In order to avoid these, please follow the design rules
listed below:
Maximize the distance among GNSS antenna, main antenna, Rx-diversity/MIMO antenna, Wi-Fi/BT
antenna, FM antenna and Wi-Fi MIMO antenna (including trace routing and antenna layout) to avoid
mutual interference.
In user systems, GNSS RF signal lines and RF components should be placed far away from high
speed circuits, switched-mode power supplies, power inductors, the clock circuit of single-chip
microcomputers, etc.
For applications with harsh electromagnetic environment or high ESD-protection requirements, it is
recommended to add ESD protective diodes for the antenna interface. Only diodes with ultra-low
junction capacitance such as 0.5pF can be selected. Otherwise, there will be effects on the
impedance characteristic of RF circuit loop, or attenuation of bypass RF signal may be caused.
Control the impedance of either feeder line or PCB trace to 50Ω, and keep the trace length as short
as possible.
Refer to Chapter 6.3 for GNSS antenna reference circuit designs.