10.3.1.3 EM2 Deep Sleep
This is the first level into the low power energy modes. Most of the high frequency peripherals are disabled or have reduced functionali-
ty. Memory and registers retain their values.
• Cortex-M4 is in sleep mode. Clocks to the core are off.
• RFSENSE available. Radio inactive
• High frequency clock tree is inactive
• Low frequency clock tree is active
• The following oscillators are available
• LFRCO, LFXO, ULFRCO, AUXHFRCO (on demand, if used by the ADC)
• The following low frequency peripherals are available
• RTCC, WDOG, LEUART, LETIMER, LESENSE, PCNT, CRYOTIMER
• The following analog peripherals are available (with potential limitations on functionality)
• ADC, IDAC, VDAC, OPAMP
• Wake-up to EM0 Active through
• Peripheral interrupt, reset pin, power on reset, asynchronous pin interrupt, I2C address recognition, or ACMP edge interrupt
• Wake-up to EM1 Sleep through
• RAC data transfer request
• Part returns to EM2 Deep Sleep when transfers are complete
• RAM and register values are preserved
• RAM blocks may be optionally powered down for lower power
• GPIO pin state is retained
• RTCC memory is retained
• The DC-DC converter can be configured to remain on in Low Power mode.
10.3.1.4 EM3 Stop
In this low energy mode, all low frequency oscillators (LFXO, LFRCO) and all low frequency clocks derived from them, are stopped, as
well as all high frequency clocks. Most peripherals are disabled or have reduced functionality. Memory and registers retain their values.
• Cortex-M4 is in sleep mode. Clocks to the core are off.
• RFSENSE available. Radio inactive
• High frequency clock tree is inactive
• All low frequency clock trees derived from the low frequency oscillators (LFXO, LFRCO) are inactive
• The following oscillators are available
• ULFRCO, AUXHFRCO (on demand, if used by the ADC)
• The following low frequency peripherals are available if clocked by the ULFRCO
• RTCC, WDOG, CRYOTIMER
• The following analog peripherals are available (with potential limitations on functionality)
• ADC, IDAC, VDAC, OPAMP
• Wake-up to EM0 Active through
• Peripheral interrupt, reset pin, power on reset, asynchronous pin interrupt, I2C address recognition, or ACMP edge interrupt
• Wake-up to EM1 Sleep through
• RAC data transfer request
• Part returns to EM3 Stop when transfers are complete
• RAM and register values are preserved
• RAM blocks may be optionally powered down for lower power
• GPIO pin state is retained
• RTCC memory is retained
• The DC-DC converter can be configured to remain on in Low Power mode.
Reference Manual
EMU - Energy Management Unit
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