| 主权项 |
1. A power management unit comprising a first voltage source, a second voltage source, and a third voltage source configured to perform a power-on sequence, wherein:
during a first time period, the voltage output from the first voltage source ramps upward, the voltage output from the second voltage source remains at a constant level, and the voltage output from the third voltage source remains at a constant level; during a second time period immediately following the first time period, the voltage output from the first voltage source remains at a constant level, the voltage output from the second voltage source remains at a constant level, and the voltage output from the third voltage source remains at a constant level; during a third time period immediately following the second time period, the voltage output from the first voltage source remains at a constant level, the voltage output from the second voltage source ramps upward, and the voltage output from the third voltage source remains at a constant level; during a fourth time period immediately following the third time period, the voltage output from the first voltage source remains at a constant level, the voltage output from the second voltage source remains at a constant level, and the voltage output from the third voltage source remains at a constant level; and during a fifth time period immediately following the fourth time period, the voltage output from the first voltage source remains at a constant level, the voltage output from the second voltage source remains at a constant level, and the voltage output from the third voltage source ramps upward. |
