Control power storage power sequence

What is a power-down sequence?

The power-down sequence is the same as power up, but in reverse order. Sequencers can be cascaded together to support many power rails, as well as provide fixed and adjustable delay times between enable signals. In Figure 4, two sequencers cascade together to achieve six sequenced rails.

Does a power-down sequence require an external IC or supervisor?

The configuration does not require an external IC or supervisor and only requires a single GPIO from the processor to sequence the power rails. Power-down sequences are not dependent on either turn-on sequence. By staying independent, the voltage rails and downstream subsystems can turn off in a different sequence than the turn-on sequence.

How do you sequence a power supply?

A basic, cost-effective way to implement sequencing is to cascade the power good (PG) pin of one power supply into the enable (EN) pin of the next sequential supply (Figure 1). The second supply begins to turn on when the PG threshold is met, usually when the supply is at 90% of its final value.

What is a 3rd Power-Sequencing configuration?

The block diagram in Figure 3 explains the configuration in more detail. The third power-sequencing configuration leaves the three load switch channels independent, which requires external control signals to control the timing sequence.

What is power down sequencing?

Power Down Sequencing This design allows users to configure multiple power sequencing configurations that are not limited to just the CT configuration and QOD configuration. The jumpers can be configured to sequence rails in other configurations, such as the ones shown in Figure 19 and Figure 20.

How does a second Power-Sequencing configuration work?

The second power-sequencing configuration also contains a single GPIO, but the configuration is only connected to the first load switch. On the output of the first load switch, QOD is connected to the enable pin of the second load switch, effectively daisy-chaining the devices together.