Renesas M32R/ECU Series User Manual page 705

17
17.1 Outline of RAM Backup Mode
In RAM backup mode, the contents of the internal RAM are retained while the power is turned off (power for only
the RAM is on). RAM backup mode is used for the following two purposes:
• Back up the internal RAM data when the power is forcibly turned off from the outside (RAM backup when the
power is down)
• For the M32R/ECU to turn off the power to the CPU at any time as needed to reduce the system's power
consumption while retaining the internal RAM data (RAM backup for saving the power consumption)
The M32R/ECU is placed in RAM backup mode by applying a voltage of 3.0–5.5 V to the VDDE pin (provided for
RAM backup) and 0 V to all other pins.
During RAM backup mode, the contents of the internal RAM are retained, while the CPU and internal peripheral I/
O remain idle. Because all pins except VDDE are held low during RAM backup mode, the power consumption in
the system can effectively be reduced.
17.1 Outline of RAM Backup Mode
17-2
RAM BACKUP MODE
32180 Group User's Manual (Rev.1.0)