Intel QX9775 EU80574XL088N データシート

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The Voltage Identification (VID) specification for the processor is defined by the Voltage 

Guidelines. The voltage set by the VID signals is the reference VR output voltage to be 

delivered to the processor Vcc pins. VID signals are open drain outputs, which must be 

pulled up to V

TT

. Refer to 

 for the DC specifications for these signals. A 

voltage range is provided in 

 and changes with frequency. The specifications 

have been set such that one voltage regulator can operate with all supported 

frequencies.

Individual processor VID values may be calibrated during manufacturing such that two 

devices at the same core frequency may have different default VID settings. This is 

reflected by the VID range values provided in 

The processor uses six voltage identification signals, VID[6:1], to support automatic 

selection of power supply voltages. 

 specifies the voltage level corresponding 

to the state of VID[6:1]. A ‘1’ in this table refers to a high voltage level and a ‘0’ refers 

to a low voltage level. If the processor socket is empty (VID[6:1] = 111111), or the 

voltage regulation circuit cannot supply the voltage that is requested, the voltage 

regulator must disable itself. See the Voltage Regulator Module (VRM) and Enterprise 

Voltage Regulator-Down (EVRD) 11.0 Design Guidelines for further details.

Although the Voltage Regulator Module (VRM) and Enterprise Voltage Regulator-Down 

(EVRD) 11.0 Design Guidelines defines VID[7:0], VID7 and VID0 are not used on the 

processor; VID7 is always hard wired low at the voltage regulator.

The processor provides the ability to operate while transitioning to an adjacent VID and 

its associated processor core voltage (V

CC

). This will represent a DC shift in the load 

line. It should be noted that a low-to-high or high-to-low voltage state change may 

result in as many VID transitions as necessary to reach the target core voltage. 

Transitions above the specified VID are not permitted. 

 includes VID step 

sizes and DC shift ranges. Minimum and maximum voltages must be maintained as 

shown in 

.

The VRM or EVRD used must be capable of regulating its output to the value defined by 

the new VID. DC specifications for dynamic VID transitions are included in 

 

and 

. Refer to the Voltage Regulator Module (VRM) and Enterprise Voltage 

Regulator-Down (EVRD) 11.0 Design Guidelines for further details.

Power source characteristics must be assured to be stable whenever the supply to the 

voltage regulator is stable.