SLVS950I July 2009 – May 2018 TPS65070 , TPS65072 , TPS65073 , TPS650731 , TPS650732
UNLESS OTHERWISE NOTED, this document contains PRODUCTION DATA.
Entry into DEEP SLEEP mode is controlled by Prima by writing to register CON_CTRL2 of TPS6507x. Before entering DEEP SLEEP mode, Prima will back up all memory and set Bit DS_RDY=1 to indicate the memory was saved and the content is valid. Setting PWR_DS=1 will turn off all voltage rails except DCDC2 for the memory voltage and the PMU will apply a reset signal by pulling PGOOD=LOW. Prima can not detect logic level change by PB_OUT going low in DEEP SLEEP mode. A wakeup from DEEP sleep is therefore managed by the PMU. The PMU will clear Bit PWR_DS and turn on the converters again based on a user “keypress” when PB_IN is being pulled LOW. Prima will now check if DS_RDY=1 to determine if the memory content is still valid and clear the Bit afterwards. In case there is a power loss and the voltage of the PMU is dropping below the undervoltage lockout threshold, the registers in the PMU are re-set to the default and DS_RDY is cleared. The PMU would perform a start-up from OFF state instead of exit from DEEP SLEEP and Sirf PRIMA would read DS_RDY=0, which indicates memory data is not valid.
See Sequence diagrams for Sirf Prima SLEEP and DEEP SLEEP in Figure 54 and Figure 55.