Power-Shutdown Sequence When Using Ram Backup - Mitsubishi Electric M32R Series User Manual

Mitsubishi 32-bit risc single-chip microcomputers

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20.3.2 Power-Shutdown Sequence When Using RAM Backup

The diagram below shows a power-shutdown sequence (5.0 V, 3.3 V power supply) of the M32R/

E when using RAM backup.

Pull the HREQ pin input low to halt the CPU at end of bus cycle. Or disable RAM access in

software. The M32R/E allows P72 to be used as HREQ irrespective of its operation mode.

With the CPU halted, pull the RESET pin input low. Or while RAM access is disabled, pull

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the RESET pin input low.

Turn off the 5 V and the 3.3 V power supply after the RESET pin goes low.

: Reduce the VDD voltage from 3.3 V to 2.0 V as necessary.

Note: Power-shutdown requirements

Figure 20.3.2 Power-Shutdown Sequence When Using RAM Backup

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