For the PDNs described in this user guide, the
PMIC has the following five configured power states:
- Standby
- Active
- MCU Only
- Pwr SoC Error
- Retention (GPIO and DDR)
In Figure 5-1, 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 7.
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. Additionally, the
FIRST_STARTUP_DONE bit is set and VCCA OV and UV masks are cleared (which are set in
the static configurations, Table 4-8). After these
instructions are executed the PMICs wait for a valid ON Request before entering the
ACTIVE state. The definition for each power state is described below:
STANDBYThe PMIC is 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 5.3.2 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 5.3.1 is performed before the PMIC leaves the PFSM and enters the FSM state SAFE_RECOVERY.
ACTIVEThe PMIC is powered by a valid supply. The PMIC is 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. Refer to
the Section 5.3.8 sequence
description.
MCU_ONLY
The PMIC is powered by a valid supply. Only the power resources assigned to
the MCU Safety Island are on. Refer to the Section 5.3.7 sequence description.
Pwr SoC Error
The PMIC is powered by a valid supply. Only the power resources assigned to
the MCU Safety Island are on. Refer to the Section 5.3.5 sequence description. The only active trigger is 'B', requiring the PMICs
to return to the MCU_ONLY mode. The return to MCU_ONLY mode and eventually
ACTIVE mode is only recommended after the interrupts which caused the
SOC_PWR_ERROR have been cleared.
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_5 bit is set high, the PMIC enters GPIO retention state. If the
I2C_7 bit is set high, the PMIC enters DDR retention state. These bits need
to be set before a trigger for the retention state occurs. Refer to the
Section 5.3.9 sequence
description.