FW82801DBM S L6DN Intel, FW82801DBM S L6DN Datasheet - Page 164

• Manufacturer Part Number: FW82801DBM S L6DN
• Manufacturer: Intel

Specifications of FW82801DBM S L6DN

• Lead Free Status / RoHS Status: Not Compliant

Functional Description
5.12.12.4
5.12.12.5
5.12.12.6
5.12.12.7
164
VRMPWRGD Signal
This signal is connected to the processor’s VRM and is internally AND’d with the PWROK signal
that comes from the system power supply. This saves the external AND gate found in desktop
systems.
VGATE Signal
VGATE is an input from the regulator indicating that all of the outputs from the regulator are on
and within specification. When the system is performing an Intel SpeedStep transition between
performance states, the voltage regulator output may be required to change. It is not desirable,
however, that CPUPWRGD becomes deasserted during these transitions. Normally, this would
indicate to the system that a power-on reset be performed, which would invalidate the system
context. Intel ICH4 prevents this from occurring by maintaining CPUPWRGOOD during the
transition. CPUPWRGOOD must also be maintained during an S1-M state.
BATLOW# - Battery Low
The BATLOW# input can inhibit waking from a sleep state if there is not sufficient power. It will
also cause an SMI# if the system is already in an S0 state.
Controlling Leakage and Power Consumption during Low-Power
States
To control leakage in the system, various signals tri-state or go low during some low-power states.
General principles:
Based on the above principles, the following measures are taken:
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All signals going to powered down planes (either internally or externally) must be either tri-
stated or driven low.
Signals with pull-up resistors should not be low during low-power states. This is to avoid the
power consumed in the pull-up resistor.
Buses should be halted (and held) in a known state to avoid a floating input (perhaps to some
other device). Floating inputs can cause extra power consumption.
During S3 (STR), all signals attached to powered down planes will be tri-stated or driven low.
Intel
®
82801DBM ICH4-M Datasheet