Hardware+Design V1.07

Table Of Contents
Smart Machine Smart Decision
5.2.2 Minimize Power Consumption
There are two modes that SIM5320 achieves low power consumption.
Sleep mode
If peripheral equipments stops working, and there is no on air or hardware interrupts (such as GPIO
interrupts or data on UART), SIM5320 will enter sleep mode automatically. In this mode, SIM5320 can
still receive pagingvoice call or SMS from network. If USB interface of SIM5320 is connected to host
CPU, but host CPU does not support USB suspending, then SIM5320 will not enter sleep mode. After
USB is disconnected, SIM5320 will enter sleep mode.
Note: When UART interface is connected with host CPU, SIM5320 can not enter sleep mode until RXD is pulled down by
the host CPU. If the module is in the idle mode, make sure to pull the RXD to low level by host CPU. SIMCom
recommends using GPIO43 or UART_DTR to wake up the module from host CPU and to use GPIO41 or UART_RI to
wake up the host CPU. Before designing, pay attention to how to realize waking function and refer to Document[24] and
Document[25] for more detail.
Minimum functionality mode
Minimum functionality mode ceases a majority function of module, thus minimizing the power
consumption. This mode is set by the AT command which provides a choice of the functionality levels.
AT+CFUN=0: Minimum functionality
AT+CFUN=1: Full functionality (Default)
AT+CFUN=4: Disable RF function of the module (Flight mode)
If SIM5320 has been set to minimum functionality mode, the module will firstly enter sleep mode, then
the RF function and SIM card function will be closed. In this case, the serial port is still accessible, but RF
function or SIM card will be unavailable. When SIM5320 is in minimum functionality or flight mode, it
can return to full functionality by the AT command “AT+CFUN=1”.
Note: For flight mode, please refer to Chapter3.10.2.
5.3 Current Consumption
The current consumption in suspended mode and without USB connection is listed in the table below.
Here, “suspended mode” means that SIM5320 is connected to USB bus, but it does not transfer data.
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