Intel 4 620 JM80547PG0722MM Data Sheet

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The VID specification for the Pentium 4 processor is supported by the Voltage Regulator Down 
(VRD) 10.1 Design Guide for Desktop LGA775 Socket. The voltage set by the VID signals is the 
reference VR output voltage to be delivered to the processor VCC pins. A minimum voltage is 
provided in 

 and changes with frequency. This allows processors running at a higher 

frequency to have a relaxed minimum voltage specification. The specifications have been set such 
that one voltage regulator can work with all supported frequencies.

Individual processor VID values may be calibrated during manufacturing such that two devices at 
the same speed may have different VID settings.

The Pentium 4 processor uses six voltage identification signals, VID[5:0], to support automatic 
selection of power supply voltages. 

 specifies the voltage level corresponding to the state 

of VID[5:0]. A ‘1’ in this table refers to a high voltage level and a ‘0’ refers to low voltage level. If 
the processor socket is empty (VID[5:0] = x11111), or the voltage regulation circuit cannot supply 
the voltage that is requested, it must disable itself. See the Voltage Regulator Down (VRD) 10.1 
Design Guide for Desktop LGA775 Socket for more details.

Power source characteristics must be guaranteed to be stable whenever the supply to the voltage 
regulator is stable.

The LL_ID[1:0] lands are used by the platform to configure the proper loadline slope for the 
processor. LL_ID[1:0] = 00 for the Pentium 4 processor.

The VTT_SEL land is used by the platform to configure the proper V

TT

 voltage level for the 

processor. VTT_SEL = 1 for the Pentium 4 processor.

The GTLREF_SEL signal is used by the platform to select the appropriate chipset GTLREF level. 
GTLREF_SEL = 0 for the Pentium 4 processor.

LL_ID[1:0] and VTT_SEL are signals that are implemented on the processor package. That is, 
they are either connected directly to V

SS

 or are open lands.