AM2434: Battery powered in STANDBY state

Hi Daisuke,

Unfortunately, the Power Estimation Tool cannot be directly configured to represent the STANDBY state.  The closest you can do with the PET is to configure with only the DMSC on, which gives a reasonably close estimate:

Leaving the DMSC on should keep the SRAM powered and preserved.

Thanks,
Mike

Hi,

I recommend taking a look at the AM243x Technical Reference Manual, section 5.2 Power, as it has additional details.

Daisuke Maeda said:

Is the AM243x required to reboot to transition from STANDBY to ACTIVE state?

Figure 5-591 in the TRM shows that transitioning from STANDBY to ACTIVE is done with an IRQ

Daisuke Maeda said:

Is the information on the 2MB OCSRAM maintained while the AM243x transitions from STANDBY to ACTIVE state?

Yes, the DMSC retains power to RAM during STANDBY and ACTIVE states, and the transitions between these two states.

Daisuke Maeda said:

Are all power terminals required to be powered ON while the AM243x is in STANDBY state?

Other than any power rails for peripherals that are not needed and are shown as ok to leave unpowered in the AM243x Datasheet, section 6.4, Pin Connectivity Requirements, yes, all power rails need to stay powered while in STANDBY.

Daisuke Maeda said:

Is the information on the 2MB OCSRAM held when AM243x is in OFF state?

No.  Section 5.2.3.1 of the TRM says that the device enters the OFF state by shutting down the power rails.  If there is no power to the device, the contents of RAM are not held.

Daisuke Maeda said:

Is the AM243x required to reboot to transition from OFF to ACTIVE state?

Yes, since the OFF state is unpowered, rebooting is required when power is supplied back to the device and it transitions back to the ACTIVE state.

Daisuke Maeda said:

Is the information on the 2MB OCSRAM maintained while the AM243x transitions from OFF to ACTIVE state?

Because the contents of RAM are not held while in OFF, there is no valid data to hold during the transition from OFF to ACTIVE.

Daisuke Maeda said:

Are all power terminals required to be powered OFF while the AM243x is in OFF state?

You should follow the Power Down sequencing shown in section 7.10.2.2.2 of the datasheet, which shows all rails going to 0V during power down.

Daisuke Maeda said:

Can the AM243x be maintained the information on the 2MB OCSRAM by powering ON only one or some power terminals?

You should always follow the Power Up and Power Down sequencing shown in sections 7.10.2.2.1 and 7.10.2.2.2 of the datasheet, which do not show a valid power scenario where some of the rails are powered on but not all that is not part of a transition.

Thanks,
Mike

Hi,

Looks like the DMSC is in the "always on" section of the Power Estimation Tool, so you can set the M4F utilization to 0% for STANDBY power estimation.

Thanks,
Mike

Hi,

Yes, any IO and Peripherals that you are not using can be set to Off.  However, keep in mind that you will want something active to wake the device from STANDBY, so what you are intending to use is one of the listed IO/peripherals, you will want to keep that one On.

Thanks,
Mike