As noted earlier, the MxL7704 uses a flexible conditional sequencing engine. Power up and power down sequencing is controlled by setting registers via I²C. Each channel (BUCK or LDO) can be assigned to be in any of four sequencing groups (GROUP 0 thru 3). The sequencing state machine starts with GROUP 0; sequencing of the next group is conditional on PGOOD of the first with a 2 ms delay. The SEQ_EN input pin gates the sequencing at the group it is assigned. Two example sequencing scenarios are illustrated here. In the first example, Buck 4 is assigned to Sequencing Group 0 and therefore powers up first, followed by the LDO in Group 1, then Buck 2 in Group 2, and finally Bucks 1 and 3 are in Group 3 and power up last. In the second example, all four bucks and the LDO are assigned to Group 1 and power up simultaneously. Power down sequencing of channels follows the reverse order of power up sequencing of channels (GROUP 3 thru 0). All channels will be sequenced down in one of the two methods, depending on the Soft Off Enable Setting: Soft Off is enabled: Dynamically slewed down for Xms (where X = Vout) then discharged through the 78 Ω resistor (default). Soft Off is disabled: All channels will be immediately tri-stated and will be discharged by the 78 Ω active discharge resistance.