M16C6N4 Datasheet, PDF (363/406 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/60 SERIES

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M16C/6N Group (M16C/6N4)
• Suggestions to reduce power consumption.
23. Usage Precaution
Ports
The processor retains the state of each I/O port even when it goes to wait mode or to stop mode.
A current flows in active I/O ports. A pass current flows in input ports that high-impedance state.
When entering wait mode or stop mode, set non-used ports to input and stabilize the potential.
A/D converter
When A/D conversion is not performed, set the VCUT bit in the ADCON1 register to “0” (VREF not
connection). When A/D conversion is performed, start the A/D conversion at least 1 µs or longer after
setting the VCUT bit to “1” (VREF connection).
D/A converter
When not performing D/A conversion, set the DAiE bit (i = 0, 1) in the DACON register to “0” (input
disabled) and DAi register to “00h”.
Stopping peripheral functions
Use the CM02 bit in the CM0 register to stop the unnecessary peripheral functions during wait mode.
However, because the peripheral function clock (fC32) generated from the sub-clock does not stop, this
measure is not conducive to reducing the power consumption of the chip. If low speed mode or low power
dissipation mode is to be changed to wait mode, set the CM02 bit to “0” (do not peripheral function clock
stopped when in wait mode), before changing wait mode.
Switching the oscillation-driving capacity
Set the driving capacity to “LOW” when oscillation is stable.
Rev.2.30 Oct 24, 2005 page 345 of 376
REJ09B0009-0230