hardware design v1.00
Table Of Contents
- Contents
- Version History
- 1 Introduction
- 2 SIM968 Overview
- 3 Package Information
- 4 GSM Application Interface
- 4.1 GSM Power Supply
- 4.2 Power on/down Scenarios
- 4.3 Power Saving Mode
- 4.4 Charging Interface
- 4.5 RTC Backup
- 4.6 Serial Interfaces
- 4.7 Audio Interfaces
- 4.8 SIM Card Interface
- 4.9 LCD Display/SPI Interface
- 4.10 Keypad Interface
- 4.11 ADC
- 4.12 RI Behaviors
- 4.13 Network Status Indication
- 4.14 General Purpose Input/Output (GPIO)
- 4.15 External Reset
- 4.16 PWM
- 4.17 I2C Bus
- 4.18 GSM Antenna Interface
- 5 GNSS Application Interface
- 6 Electrical, Reliability and Radio Characteristics
- 6.1 Absolute Maximum Ratings
- 6.2 Recommended Operating Conditions
- 6.3 Digital Interface Characteristics
- 6.4 SIM Card Interface Characteristics
- 6.5 VDD_EXT Characteristics
- 6.6 SIM_VDD Characteristics
- 6.7 VRTC Characteristics
- 6.8 Current Consumption (VBAT = 3.8V)
- 6.9 Electro-Static Discharge
- 6.10 Radio Characteristics
- 6.11 Module label information
- Appendix
Smart Machine Smart Decision
Figure 10: Powered on/down module using button
The power on scenarios is illustrated as following figure.
Figure 11: Timing of power on module
When power on procedure is completed, SIM968 will send following URC to indicate that the module is ready to
operate at fixed baud rate.
RDY
This URC does not appear when autobauding function is active.
Note: User can use AT command “AT+IPR=x” to set a fixed baud rate and save the configuration to non-volatile flash memory.
After the configuration is saved as fixed baud rate, the Code “RDY” should be received from the serial port every time when
SIM968 is powered on. For details, please refer to the chapter “AT+IPR” in document [1].
4.2.1.2 Turn on the SIM968 using the VCHG Signal
The SIM968 will be automatically turned on when a charger is connected to the switched-off SIM968 of which
VBAT pin voltage is greater than 3.2V. SIM968 will go into the Charge-only Mode. In this mode, the module
does not register to the network, and has only a few AT commands available.
When module is powered on using the VCHG signal, SIM968 sends out result code as following when fixed
baud rate set:
RDY
CHARGE-ONLY MODE
When user drives the PWRKEY of Charge-only mode SIM968 to a low level voltage for a period of time (please
refer to Figure 12 Timing of power on module), the SIM968 will power up and go into Charge mode during
normal operation. In this case, SIM968 sends out result code as following:
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