Hello, the LTM4681 and LTM4682 datasheets claim the devices can be configured 3+1 phase, however, there are no design examples of this phase arrangement. There is a subtle difference between the two devices in table 3 of the datasheets; for the LTM4681, FSWPH_CFG_01 applies to phase 0 only and FSWPH_CFG_23 applies to phase 1 only. On the LTM4682, FSWPH_CFG_01 applies to phases 0 and 2 and FSWPH_CFG_23 applies to phases 1 and 3. It appears the LTM4681 can achieve 3+1, assuming that channels 2 and 3 remain fixed at 0 phase, by selecting 120 and 240 for phases 0 and 1 respectively, and combining channels 0-2 into one rail with channel 3 as the other rail. This does not appear to be possible with the LTM4682, since phases are set in pairs by each strap according to table 3, hence there will be no (3rd) 0-phase channel. It appears the only way to achieve 3+1 phase arrangement is through NVM configuration. Please confirm my understanding of this.
