Datasheet

Section 24 Power-Down State
Rev. 4.00 Jun 06, 2006 page 697 of 1004
REJ09B0301-0400
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 24.3 Software Standby Mode Application Example
24.6.5 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.
24.7 Hardware Standby Mode
24.7.1 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.