ZHCSD04E November 2014 – March 2022 TPS65400
PRODUCTION DATA
The default settings for SEQUENCE_ORDER (see (D5h SEQUENCE_ORDER)) effectively disable sequencing by setting all switchers to start at the same time. Therefore, to use internal sequencing, the default values for SEQUENCE_ORDER must be changed to the desired sequence. In addition, the user can configure the start or stop sequence to have a dependence on the PGOOD output of the previous switcher, or to wait for a set delay. If configured to have a dependence on PGOOD, the soft-start for the next switcher begins after PGOOD of the previous goes high and the wait time determined by tON_DELAY is complete. If configured to wait for a set delay, the wait time determined by tON_DELAY begins immediately upon the enabling of the previous switcher.
In addition, each supply can be disabled such that it is bypassed in the power-up sequence. For example, if the sequence is SW1-SW2-SW3-SW4, and SW2 is disabled, then SW3 will be powered up after SW1. The initial configuration of the TPS65400 (for first-time power-up) needs to be done using one of the methods described in Section 8.3.14.