1628 - Power Manager II: When using the trim functions of a POWR6AT6, or POWR1220 what happens if I separately disable the LDO or DC-to-DC converter being controlled?
If you disable an LDO or DC-to-DC converter being trimmed bya POWR6AT6 or POWR1220, their trim circuitry will still attempt to perform the trim operation, except that it will now see '0' V as the feedback voltage. This will result in the TRIM output moving to a 'maximum output' command condition, so when you re-enable the LDO or DC-to-DC it will be at maximum output voltage, and then drop back to the desired trim target. To avoid this problem you need to disable the trim function whenever the controlled converters are disabled.