H83637S Datasheet, PDF (101/418 Pages) Renesas Technology Corp – 8-Bit Microcomputer

Section 5 Power-Down Modes
5.1 Overview
The H8/3637S Series has seven modes of operation after a reset. These include six power-down
modes, in which power dissipation is significantly reduced.
Table 5.1 gives a summary of the seven operation modes.
Table 5.1 Operation Modes
Operating Mode
Active (high-speed) mode
Active (medium-speed) mode
Subactive mode
Sleep mode
Subsleep mode
Watch mode
Standby mode
Description
The CPU runs on the system clock, executing program
instructions at high speed
The CPU runs on the system clock, executing program
instructions at reduced speed
The CPU runs on the subclock, executing program instructions
at reduced speed
The CPU halts. On-chip peripheral modules continue to operate
on the system clock.
The CPU halts. Timer A, and timer G, continue to operate on
the subclock.
The CPU halts. The time-base function of Timer A continues to
operate on the subclock.
The CPU and all on-chip peripheral modules stop operating
All but the active (high-speed) mode are power-down modes.
In this section the two active modes (high-speed and medium-speed) are referred to collectively as
active mode.
Figure 5.1 shows the transitions among these operation modes. Table 5.2 indicates the internal
states in each mode.
87