Datasheet

Section 6 Power-Down Modes
Rev. 1.50 Sep. 18, 2007 Page 89 of 584
REJ09B0240-0150
Section 6 Power-Down Modes
This LSI has five operating modes after a reset: a normal active mode and four power-down
modes in which power consumption is significantly reduced. In addition to these modes, there is a
module standby function in which power consumption is also reduced by selectively halting on-
chip module functions.
• Active mode
The CPU and all on-chip peripheral modules operate on the system clock. The system clock
source can be selected from among φosc, Rosc/2, Rosc/4, and Rosc/8. The system clock
frequency can be selected from among φ, φ/8, φ/16, φ/32, and φ/64.
• Subactive mode
The CPU and all on-chip peripheral modules operate on the subclock. The subclock frequency
can be selected from φw/2, φw/4, or φw/8.
• Sleep mode
The CPU halts. On-chip peripheral modules operate on the system clock.
• Subsleep mode
The CPU halts. On-chip peripheral modules operate on the subclock.
• Standby mode
The CPU and all on-chip peripheral modules halt. When the clock time-base function is
selected, the RTC operates.
• Module standby function
Independent of the above modes, power consumption can be reduced by halting individual on-
chip peripheral modules that are not in use.