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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Table 37: GNSS Frequency
Type
Frequency
Unit
GPS
1575.42±1.023
MHz
GLONASS
1597.5~1605.8
MHz
BeiDou
1561.098±2.046
MHz
6.3.1. Recommended Circuit for Passive Antenna
GNSS antenna interface supports passive ceramic antennas and other types of passive antennas. When
the passive antenna is placed far away from the module (that is, the antenna trace is long), it is
recommended to add an external LNA circuit for better GNSS receiving performance, and the LNA should
be placed close to the antenna. A reference circuit design is given below.
Figure 37: Reference Circuit Design for GNSS Passive Antenna
6.3.2. Recommended Circuit for Active Antenna
The active antenna is powered by VCC power supply through the R1 and L1 power paths shown in the
following figure. The common power supply voltage ranges from 3.3V to 5.0V. Although featuring low
power consumption, the active antenna still requires stable and clean power supplies. It is recommended
to use high performance LDO as the power supply. A reference design of GNSS active antenna is shown
below.