Datasheet

Datasheet 19
Electrical Specifications
3 Electrical Specifications
3.1 Power and Ground Pins
For clean, on-chip power distribution, the processor has a large number of V
CC
(power)
and V
SS
(ground) inputs. All power pins must be connected to V
CC
power planes while
all V
SS
pins must be connected to system ground planes. Use of multiple power and
ground planes is recommended to reduce I*R drop. The processor V
CC
pins must be
supplied the voltage determined by the VID (Voltage ID) pins.
3.2 FSB Clock (BCLK[1:0]) and Processor Clocking
BCLK[1:0] directly controls the FSB interface speed as well as the core frequency of the
processor. As in previous generation processors, the processor core frequency is a
multiple of the BCLK[1:0] frequency. The processor uses a differential clocking
implementation.
3.3 Voltage Identification
The processor uses seven voltage identification pins,VID[6:0], to support automatic
selection of power supply voltages. The VID pins for processor are CMOS outputs
driven by the processor VID circuitry. Tab l e 2 specifies the voltage level corresponding
to the state of VID[6:0]. A 1 refers to a high-voltage level and a 0 refers to low-voltage
level.
Table 2. Voltage Identification Definition (Sheet 1 of 4)
VID6 VID5 VID4 VID3 VID2 VID1 VID0 V
CC
(V)
0 0 0 0 0 0 0 1.5000
0 0 0 0 0 0 1 1.4875
0 0 0 0 0 1 0 1.4750
0 0 0 0 0 1 1 1.4625
0 0 0 0 1 0 0 1.4500
0 0 0 0 1 0 1 1.4375
0 0 0 0 1 1 0 1.4250
0 0 0 0 1 1 1 1.4125
0 0 0 1 0 0 0 1.4000
0 0 0 1 0 0 1 1.3875
0 0 0 1 0 1 0 1.3750
0 0 0 1 0 1 1 1.3625
0 0 0 1 1 0 0 1.3500
0 0 0 1 1 0 1 1.3375
0 0 0 1 1 1 0 1.3250
0 0 0 1 1 1 1 1.3125
0 0 1 0 0 0 0 1.3000
0 0 1 0 0 0 1 1.2875
0 0 1 0 0 1 0 1.2750
0 0 1 0 0 1 1 1.2625
0 0 1 0 1 0 0 1.2500
0 0 1 0 1 0 1 1.2375