Recommended power saving configuration

The commands in Table 4-9 select the power mode and the use model. The settings below reduce current further by disabling functions that an application in the field does not need. Apply them once during provisioning, and verify each returns OK before continuing.


      AT+IPR=9600                       // use LPUART 
      OK 
      <= change terminal software to 9600 bps => 
      AT%MODULECFG="ledMode",0          // disable LEDs 
      OK 
      AT%MODULECFG="logCtrl",0          // disable log output 
      OK 
      AT%MODULECFG="usbCtrl",2          // disable USB 
      OK 
      AT%MODULECFG="usbSlpMask",1       // mask USB voting 
      OK 
      AT%SIMCFG="SimPowerSave",1        // enable SIM power save 
      OK 
      AT%SIMCFG="SimPresenceDetect",0   // disable SIM detection 
      OK

Order matters for the first command. AT+IPR=9600 takes effect immediately, so the terminal or host UART must change to 9 600 bps before the remaining commands are sent.

Table 7. Recommended power saving settings
Command	Effect
AT+IPR=9600	Set UART1 baud rate to 9600 bps, which enables low-power UART operation and makes UART incoming data available as a wake source. Required for System OFF. See 4.4.2 for the alternative when the design must keep UART1 at 115,200 bps.
AT%MODULECFG="ledMode",0	Disable the STATUS and NETWORK indicator outputs. See 8.1.
AT%MODULECFG="logCtrl",0	Disable modem trace output. See 10.
AT%MODULECFG="usbCtrl",2	Disable the USB device interface.
AT%MODULECFG="usbSlpMask",1	Mask USB from the sleep vote, so an attached USB host does not hold the module awake.
AT%SIMCFG="SimPowerSave",1	Enable SIM power saving.
AT%SIMCFG="SimPresenceDetect",0	Disable SIM presence detection.

"SimPresenceDetect",0 disables SIM hot-swap detection, so SIM presence transitions no longer wake the module. Leave presence detection enabled on designs with a user-accessible SIM slot that must respond to a card being inserted or removed.

"usbCtrl",2 disables the USB device interface. Designs that rely on USB VBUS detect as a wake source, or that use USB for AT control, network data, or trace, should leave USB enabled and use usbSlpMask alone to prevent USB from holding the module awake.

Note: Disabling trace output with "logCtrl",0 also disables the diagnostic stream that Nordic technical support uses. Re-enable it before capturing a trace for a support case.