M30102 datasheet(28/164 Pages) RENESAS

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Power Control

Under

development

Tentative Specifications REV.E1

Specifications in this manual are tentative and subject to change.

Mitsubishi microcomputers

M30100/M30102 Group

SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

Power Control

This section gives an overview of power control.

Modes

There are three power save modes.

(1) Normal operating mode

• High-speed mode

In this mode, one main clock cycle forms BCLK. The CPU operates on the BCLK. The peripheral

functions operate on the clocks specified for each respective function.

• Medium-speed mode

In this mode, the main clock is divided into 2, 4, 8, or 16 to form BCLK. The CPU operates on the

BCLK. The peripheral functions operated on the clocks specified for each respective function.

• Low-speed mode

In this mode, fc forms BCLK. The CPU operates on the fc clock. fc is the clock supplied by the

subclock. The peripheral functions operate on the clocks specified for each respective function.

• Low power-dissipation mode

This mode is selected when the main clock is stopped from low-speed mode. The CPU operates on

the fc clock. fc is the clock supplied by the subclock. Only the peripheral functions for which the

subclock was selected as the count source continue to run.

• Ring oscillator mode

This mode sets the ring oscillator as BCLK. The ring oscillator can be set to no division, 2-divisions, 4-

division, 8-division, or 16-division mode according to the settings for CM06, CM16, and CM17. In-

creasing the division ratio lowers power consumption. When the microcomputer is operating with the

ring oscillator, the XIN clock driver can be stopped by setting the main clock stop bit to “1.” This can

lower the power dissipation even more.

(2) Wait mode

CPU operation is halted in this mode. The oscillator continues to run.

(3) Stop mode

All oscillators stop in this mode. The CPU and internal peripheral functions all stop. Of all 3 power

saving modes, power savings are greatest in this mode. The mode cannot be shifted to the stop mode

directly from the ring oscillator mode.

Figure 1.9.1 and 1.9.2 show the transition between each of the three modes, (1), (2), and (3).

M30102 Datasheet(PDF) 28 Page - Renesas Technology Corp