Intel Atom Processor N270 AU80586GE025D Data Sheet

Product codes
AU80586GE025D
Page of 57
 
Low Power Features 
 
 
Datasheet  
 15 
While in the Sleep state, the processor is capable of entering an even lower power 
state, the Deep Sleep state, by asserting the DPSLP# pin (see Section 
2.1.2.5). While 
the processor is in the Sleep state, the SLP# pin must be de-asserted if another 
asynchronous FSB event needs to occur.  
2.1.2.5 
Deep Sleep State 
The Deep Sleep state is entered through assertion of the DPSLP# pin while in the 
Sleep state. BCLK may be stopped during the Deep Sleep state for additional platform 
level power savings. BCLK stop/restart timings on appropriate chipset-based platforms 
with the CK505 clock chip are as follows: 
• 
Deep Sleep entry: the system clock chip may stop/tri-state BCLK within 2 BCLKs 
of DPSLP# assertion. It is permissible to leave BCLK running during Deep Sleep. 
• 
Deep Sleep exit: the system clock chip must start toggling BCLK within 10 BCLK 
periods within DPSLP# de-assertion. 
To re-enter the Sleep state, the DPSLP# pin must be de-asserted. BCLK can be re-
started after DPSLP# de-assertion as described above. A period of 15 microseconds 
(to allow for PLL stabilization) must occur before the processor can be considered to 
be in the Sleep state. Once in the Sleep state, the SLP# pin must be de-asserted to 
re-enter the Stop-Grant state. 
While in Deep Sleep state, the processor is incapable of responding to snoop 
transactions or latching interrupt signals. No transitions of signals are allowed on the 
FSB while the processor is in Deep Sleep state. When the processor is in Deep Sleep 
state, it will not respond to interrupts or snoop transactions. Any transition on an 
input signal before the processor has returned to Stop-Grant state will result in 
unpredictable behavior. 
2.1.2.6 
Deeper Sleep State 
The Deeper Sleep state is similar to the Deep Sleep state but further reduces core 
voltage levels. One of the potential lower core voltage levels is achieved by entering 
the base Deeper Sleep state. The Deeper Sleep state is entered through assertion of 
the DPRSTP# pin while in the Deep Sleep state. The following lower core voltage level 
is achieved by entering the Intel Enhanced Deeper Sleep state which is a sub-state of 
Deeper Sleep state. Intel Enhanced Deeper Sleep state is entered through assertion of 
the DPRSTP# pin while in the Deep Sleep only when the L2 cache has been completely 
shut down. Refer to Section 2.1.2.6.1 for further details on reducing the L2 cache and 
entering Intel Enhanced Deeper Sleep state. 
In response to entering Deeper Sleep, the processor drives the VID code 
corresponding to the Deeper Sleep core voltage on the VID [6:0] pins.  
Exit from Deeper Sleep or Intel Enhanced Deeper Sleep state is initiated by DPRSTP# 
de-assertion when the core requests a package state other than C4 or the core 
requests a processor performance state other than the lowest operating point.  
2.1.2.6.1  Intel Enhanced Deeper Sleep State 
Intel Enhanced Deeper Sleep state is a sub-state of Deeper Sleep that extends power 
saving capabilities by allowing the processor to further reduce core voltage once the