Specifications

PENTIUM® PRO PROCESSOR AT 150, 166, 180, and 200 MHz E
16
A20M#
IGNNE#
LINT1/NMI
LINT0/INTR
Set Ratio:
P6
CRESET#
P6
P6
Pentium
®
Pro
Processor
1KΩ
3.3V
Mux
1KΩ
3.3V
Figure 10. Example Schematic for Clock Ratio Pin Sharing
Note:
In order to support different frequency
multipliers to each processor, the design
shown above would require four multiplexers
3.6. Voltage Identification
There are four Voltage Identification Pins on the
Pentium Pro processor package. These pins can be
used to support automatic selection of power supply
voltage. These pins are not
signals but are each
either an open circuit in the package or a short circuit
to V
SS
.
The opens and shorts define the voltage required by
the processor. This has been added to cleanly
support voltage specification variations on future
Pentium Pro processors. These pins are named
VID0 through VID3 and the definition of these pins is
shown in Table 1. A ‘1’ in this table refers to an open
pin and ‘0’ refers to a short to ground. The V
CC
P
power supply should supply the voltage that is
requested
or disable itself.
Table 1. Voltage Identification Definition
1,2
VID[3:0]
Voltage
Setting
VID[3:0]
Voltage
Setting
0000 3.5
1000
2.7
0001 3.4
1001
2.6
0010 3.3
1010
2.5
0011 3.2
1011
2.4
0100 3.1
1100
2.3
0101 3.0
1101
2.2
0110 2.9
1110
2.1
0111 2.8
1111
No CPU
Present
NOTES:
1. Nominal setting requiring regulation to ±5% at the
Pentium
®
Pro processor V
CC
P pins under all
conditions. Support not expected for 2.1V—2.3V.
2.
1= Open circuit; 0= Short to V
SS