| 摘要 |
<p>PURPOSE: To provide a power management system optimizing the power management in a computer system using an integrated processor. CONSTITUTION: When the computer system is reset, the power management unit 208 enters a ready state at which a CPU clock signal and a system clock signal are driven at the maximum frequency. When a primary activity is not detected within a time, the power management unit transits from the ready state, to a pause state where a frequency of the CPU clock signal is reduced, a standby state where the CPU clock signal is stopped, and a holding state where both the CPU clock signal and the system clock signal are stopped and power supply to selected circuit sections is stopped continuously. When a secondary activity is detected in the pause state or the ready state, the power management unit enters a transient state where both the CPU clock signal and the system clock signal are driven at a maximum frequency for a predetermined time.</p> |
