Product Info
Table Of Contents
- About the Document
- Contents
- Table Index
- Figure Index
- 1Introduction
- 2Product Concept
- 3Application 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 Interface
- 3.10.UART Interfaces
- 3.11.(U)SIM Interfaces
- 3.12.SD Card Interface
- 3.13.GPIO Interfaces
- 3.14.I2C Interfaces
- 3.15.ADC Interfaces
- 3.16.Motor Drive Interface
- 3.17.LCM Interface
- 3.18.Touch Panel Interface
- 3.19.Camera Interfaces
- 3.20.Sensor Interfaces
- 3.21.Audio Interfaces
- 3.22.Emergency Download Interface
- 4Wi-Fi and BT
- 5GNSS
- 6Antenna Interface
- 7Electrical, Reliability and Radio Characteristics
- 8Mechanical Dimensions
- 9Storage, Manufacturing and Packaging
- 10Appendix A References
- 11Appendix B GPRS Coding Schemes
- 12Appendix C GPRS Multi-slot Classes
- 13Appendix D EDGE Modulation and Coding Schemes
Smart LTE Module Series
SC20 Hardware Design
SC20_Hardware_Design Confidential / Released
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Figure 35: Coplanar Waveguide Line Design on a 4-layer PCB (Layer 4 as Reference Ground)
In order to ensure RF performance and reliability, the following principles should be complied with in RF
layout design:
Use impedance simulation tool to control the characteristic impedance of RF traces as 50Ω.
The GND pins adjacent to RF pins should not be designed as thermal relief pads, and should be fully
connected to ground.
The distance between the RF pins and the RF connector should be as short as possible, and all the
right angle traces should be changed to curved ones.
There should be clearance area under the signal pin of the antenna connector or solder joint.
The reference ground of RF traces should be complete. Meanwhile, adding some ground vias around
RF traces and the reference ground could help to improve RF performance. The distance between
the ground vias and RF traces should be no less than two times the width of RF signal traces (2*W).
For more details about RF layout, please refer to document [4].
6.2. Wi-Fi/BT Antenna Interface
The following tables show the pin definition and frequency specification of the Wi-Fi/BT antenna interface.
Table 34: Pin Definition of Wi-Fi/BT Antenna Interface
Pin Name
Pin No.
I/O
Description
Comment
ANT_WIFI/BT
77
IO
Wi-Fi/BT antenna interface
50Ω impedance