Datasheet

Section 25 Power-Down State
Rev. 4.00 Sep 27, 2006 page 759 of 1130
REJ09B0327-0400
Oscillator
φ
NMI
NMIEG
SSBY
NMI
exception
handling
NMIEG = 1
SSBY = 1
SLEEP instruction
Software standby mode
(power-down state)
Oscillation
settling time
t
OSC2
NMI exception
handling
Figure 25.3 Software Standby Mode Application Example
25.6.5 Usage Note
In software standby mode, I/O port states are retained. Therefore, there is no reduction in current
dissipation for the output current when a high-level signal is output.
Current dissipation increases while waiting for oscillation to settle.
25.7 Hardware Standby Mode
25.7.1 Hardware Standby Mode
When the STBY pin is driven low, a transition is made to hardware standby mode from any mode.
In hardware standby mode, all functions enter the reset state and stop operation, resulting in a
significant reduction in power dissipation. As long as the prescribed voltage is supplied, on-chip
RAM data is retained. I/O ports are set to the high-impedance state.