hardware design v1.00

Table Of Contents
Smart Machine Smart Decision
z Receive a voice or data call from network.
z Receive a SMS from network.
4.3.4 Sleep Mode 2 (AT+CSCLK=2)
AT+CSCLK=2 can set module to the sleep mode 2.
In this mode, SIM968 will continuously monitor the serial port data signal. When there is no data transfer over 5
seconds on the RXD signal and there is no on air and hardware interrupts (such as GPIO interrupt), SIM968 will
enter sleep mode 2 automatically. In this mode, SIM968 can still receive paging or SMS from network but the
serial port is not accessible.
Note: For SIM968, It is requested to set AT command “AT+CSCLK=2” to enable the sleep mode 2; the default value is 0, which
can not make the module to enter sleep mode. For more details please refer to document [1].
4.3.5 Wake Up SIM968 from Sleep Mode 2 (AT+CSCLK=2)
When SIM968 is in sleep mode 2 (AT+CSCLK=2), the following methods can wake up the module:
z Send data to SIM968 via main serial port.
*
z Receive a voice or data call from network.
z Receive a SMS from network.
Note: The first byte of the user’s data will not be recognized.
4.4 Charging Interface
SIM968 has integrated a charging circuit inside the module for Li-Ion batteries charging control, which make it
very convenient for user’s applications that support battery charging. A common connection is shown in the
following figure:
Module
Battery Pack
R
TEMP
Thermistor
TEMP_BAT
V
BAT
V
CHG
5V
Figure 14: SIM968 with battery charger and pack connection
Battery temperature measurement is a customization function which is supported by the software in the module.
In above figure, the R
TEMP
is a NTC thermistor, and it is recommended to use MURATA NCP15XH103F03RC.
Its impedance is 10Kohm at 25. Refer to the above figure for the reference circuit.
SIM968_Hardware Design_V1.00 2013.02.25
24