In this PDN, the PMIC has the following configured
power states:
Standby
Active
Retention (both DDR and GPIO retention modes)
In Figure 6-1, the configured PDN power states are shown, along with the transition conditions to move between the states. Additionally, the transitions to hardware states, such as SAFE RECOVERY and LP_STANDBY are shown. The hardware states are part of the fixed device power Finite State Machine (FSM) and described in the TPS6594-Q1 data sheet, see Section 8.
Figure 6-1 Pre-Configurable Finite State Machine (PFSM) Mission States and Transitions
When the PMIC transitions from the FSM to the
PFSM, several initialization instructions are performed to disable the residual voltage
checks on both the BUCK and LDO regulators and set the FIRST_STARTUP_DONE bit. After these
instructions are executed the PMIC waits for a valid ON Request before entering the ACTIVE
state. The definition for each power state is described below:
STANDBYThe PMICs are powered by a valid supply on the system power rail (VCCA > VCCA_UV). All device resources are powered down in the STANDBY state. EN_DRV is forced low in this state. The processor is in the Off state, no voltage domains are energized. Refer to the Section 6.3.2 sequence description.The STANDBY state is also entered when an error occurs and the PMIC transitions out of the PFSM mission states and into the FSM states. When the device returns from the FSM state the to PFSM the first state is represented by STANDBY with all of the resources powered down and EN_DRV forced low. The sequence Section 6.3.1 is performed before the PMIC leaves the PFSM and enters the FSM state SAFE_RECOVERY.
ACTIVEThe PMICs are powered by a valid supply. The PMICs are fully functional and supply power to all
PDN loads. The processor has completed a recommended power up sequence with all voltage
domains energized in both MCU and Main processor sections. The MCU can now set the
ENABLE_DRV bit high. Refer to the Section 6.3.4 sequence
description.
RetentionThe PMIC is powered by a valid supply. Only the power resources assigned to the retention rails
are on or in LPM depending on the specific resource setting. If a given resource is
maintained active, then all linked subsystems are automatically maintained active.
ENABLE_DRV bit is cleared by the device in this state. If the I2C_6 bit is set high, the
PMIC enters GPIO retention state. If the I2C_7 bit is set high, the PMICs enters DDR
retention state. These bits need to be set before a trigger for the retention state
occurs. Refer to the Section 6.3.5 sequence
description.