S42
Hardware User Guide
1VV0301303 Rev. 11
Page 17 of 85
2021-05-06
Not Subject to NDA
Deep Sleep power saving could be achieved by using the AT+SYSTEMOFF command.
Wake-up from deep sleep after AT+SYSTEMOFF always includes a reset cycle and a loss
of the previous operation environment. If it is desired to keep the operation environment
during power down UICP SW should be implemented in the host CPU.
If using the AT+SYSTEMOFF command in combination with wake-up via GPIO, a host
could wake-up the Sx using the UICP schemes. Alternatively, the wake-up
source ext. RESET could be configured, which results in the least possible current
consumption.
See chapters 3.3.5 Dynamic I/O Signal Type Changes Depending on UICP Status.
UART
GND
UART
B
lu
eM
o
d
+
Sx
H
o
st
GPIOx
EXT-RES#
Figure 5: Host wake-up from deep-sleep via RESET
3.3.1.1.
Wake-Up Sources AT+SYSTEMOFF
The wake-up sources are FW dependent and programmable. For detailed information
please see corresponding FW documentation. The following table gives a rough overview.
WAKE-UP
SOURCE
FW CEN
FW ADC/TWI
FW ADC/LUA
Deep Sleep
Current
PIN RESET#
YES
YES
YES
0.3µA
CTS#
YES
YES 1)
YES 1)
1.2µA
IUR-IN#
YES 2)
YES 2)
NO
1.2µA
HANGUP#
YES
NO
NO
1.2µA
DIOx
NO
YES 3)
YES 3
1.2µA
Note:
1)
Only available if UART is active
2)
Only available if UICP is active
3)
Only if DIOx is enabled as input
Table 4: Wake-Up Sources AT+SYSTEMOFF
