SLVUCJ9 February 2023 LP8764-Q1 , TPS6594-Q1
The C and D triggers, defined by the NSLEEPx bits or pins, trigger the TO_RETENTION sequence. This sequence disables all power rails and GPIOs that are not supplying the retention rails, as described in GUID-3D986E78-4B9F-400A-8AD5-867276DE7360.html#FIG_XHW_CCV_HVB. The sequence can be modified using the I2C_5, I2C_6, and I2C_7 bits found in register FSM_I2C_TRIGGERS. These bits need to be set by I2C in both PMICs before a trigger for the retention state occurs. If the I2C_5, I2C_6, and I2C_7 bits are set high in all PMICs, they enter the DDR and GPIO retention state as shown in #GUID-D279015F-F742-432A-9BDF-5FDB7EBB0F89. If I2C_5, I2C_6, and I2C_7 are set low, these components associated with DDR and GPIO retention do not remain active, as shown in #GUID-0C2AA040-36FC-40A7-AD07-1457526373CD.
The following PMIC PFSM instructions are executed automatically in the beginning of the power sequence to configure the PMICs:
// TPS65941120
// Set LPM_EN, Clear NRSTOUT_SOC and NRSTOUT
REG_WRITE_MASK_IMM ADDR=0x81 DATA=0x04 MASK=0xF8
// Set SPMI_LP_EN and FORCE_EN_DRV_LOW
REG_WRITE_MASK_IMM ADDR=0x82 DATA=0x18 MASK=0xE7
// TPS65941421 LP876411B5
// Set SPMI_LP_EN
REG_WRITE_MASK_IMM ADDR=0x82 DATA=0x10 MASK=0xEF
At the end of the sequence, both PMICs set the LPM_EN and clear the CLKMON_EN and AMUXOUT_EN. The TPS65941120 device also performs an additional 16 ms delay based upon the contents of the register (PFSM_DELAY_REG_2) to ensure that the TPS65941120 sequence finishes last.