Semtech LR1110 - Table 2-3: Sleepconfig Parameter; Table 2-4: Sleep Mode Summary

LR1110
User Manual Rev.1.0
UM.LR1110.W.APP March 2020
16 of 130
Semtech
www.semtech.com
• The SleepConfig bits define in which sleep mode the device is put, and if it wakes up after a given time on the RTC
event:
 Retention bit (bit 0) defines if the device configuration and the firmware data are retained.
 Retention=1: 8 kB of memory used for device state and firmware data retention.
 Retention=0: no data retention.
 Wakeup bit (bit 1) determines if the device wakes up after a given time on the RTC event.
 Wakeup=1: automatic wake-up enabled. The device will automatically go in Standby mode with RC oscillator, at
the end of the SleepTime timer. The 32 kHz clock source is configured using the command ConfigLFclock ( ) for
modem applications.
 Wakeup=0: automatic wake-up disabled.
 Other bits are RFU and should be set to 0.
• SleepTime: sleep time in number of 32.768 kHz clock cycles, prior to automatic wake-up. Therefore, the sleep time can
vary from 0 ms to 36.4 hours in steps of 30.52us.
BUSY is set to 1 in sleep mode.
The device can exit this mode based on the detection a falling edge on the NSS pin. Exiting this mode, the device will
perform a firmware restart. When the BUSY pin is set to low, it indicates that the startup phase has been performed
successfully, and that the device is ready to accept a command.
The following table summarizes the different sleep modes according to the Retention and Wakeup bits configuration, with
their current consumption and Standby transitions times (indicative values, for comparison only).
The mode Retention=1 and Wakeup=0 is a valid usage mode, but does not correspond to any datasheet description.
Table 2-3: SleepConfig Parameter
SleepConfig bit bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0
Definition RFU RFU RFU RFU RFU RFU Wakeup Retention
Table 2-4: Sleep Mode Summary
Retention Wakeup Datasheet
Indicative Consumption (uA)
RC /XTAL
Indicative Transition to Stby
(ms)
0 0 Powerdown IDDPDN 30
0 1 Sleep IDDSL1 / IDDSL2 30
1 0 - - -
1 1 Sleep w/ 8kB retention IDDSL3A / IDDSL4A <1