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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1. It is suggested that customers should switch off the power supply for module in abnormal state, and
then switch on the power to restart the module.
2. The module supports battery charging function by default. If the above power supply design is
adopted, please make sure the charging function is disabled by software, or connect VBAT to
Schottky diode in series to avoid the reverse current to the power supply chip.
3.5. Turn on and off Scenarios
3.5.1. Turn on Module Using the PWRKEY
The module can be turned on by driving PWRKEY pin to a low level for at least 1.6s. PWRKEY pin is
pulled to 1.8V internally. It is recommended to use an open drain/collector driver to control the PWRKEY.
A simple reference circuit is illustrated in the following figure.
Figure 6: Turn on the Module Using Driving Circuit
The other way to control the PWRKEY is using a button directly. A TVS component is indispensable to be
placed nearby the button for ESD protection. A reference circuit is shown in the following figure.
NOTES