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 17: Reference Circuit for (U)SIM Interface with an 8-pin (U)SIM Card Connector
If there is no need to use USIM_DETECT, please keep it open. The following is a reference circuit for
(U)SIM interface with a 6-pin (U)SIM card connector.
Figure 18: Reference Circuit for (U)SIM Interface with a 6-pin (U)SIM Card Connector
In order to ensure good performance and avoid damage of (U)SIM cards, please follow the criteria below
in (U)SIM circuit design:
Keep placement of (U)SIM card connector as close to the module as possible. Keep the trace length
of (U)SIM card signals as less than 200mm as possible.
Keep (U)SIM card signals away from RF and VBAT traces.
A 100nF filter capacitor shall be reserved for USIM_VDD, and its maximum capacitance should not
exceed 1uF. The capacitor should be placed near to (U)SIM card.
To avoid cross-talk between USIM_DATA and USIM_CLK, keep them away from each other and
shield them with ground. USIM_RST also needs ground protection.