
PRELIMINARY
151
A
PCIset Electrical Specifications
1.0
ELECTRICAL CHARACTERISTICS
This section contains the electrical characteristics associated with the Intel 450KX/GX PCIsets. This includes
information on power consumption, AC and DC signal timing information for GTL+ and non-GTL+ signals. To
ensure functionality and reliability, the Intel 450KX/GX PCIsets are specified for proper operation when TC
(case temperature) is within the specified range of 0°C to 85°C. For more information on measuring TC in your
system, please refer to the
Pentium Pro Family Developer’s Manual: Specifications. Most of the Pentium Pro
Processor signals use a variation of the low voltage GTL (Gunning Transceiver Logic). For more information on
this technology refer to the
Pentium Pro Family Developer’s Manual: Specifications.
1.1
Test Pins and Unused Pins
For reliable operation, always connect unused inputs to an appropriate signal level. Unused GTL+ inputs should
be pulled-up to VTT with a 25 to 10K resistor. Unused active low 3.3V inputs should be pulled-up to 3.3V
with a 10K
resistor. Unused active high inputs should be pulled to ground (VSS) with a 1K resistor. When
connecting bidirectional signals to power or ground, a resistor must be used. When tying any signal to power or
ground, a resistor will also allow for fully testing the processor and PCIset after board assembly. It is suggested
that ~10K
resistors be used for pull-ups and ~1K resistors be used as pull-downs.
In the 450KX/GX QFP and BGA Pinlists, in Section 3.0 of Chapter 2 and Chapter 3, all signals labeled
“TESTLO” should be pulled to GND with a 1K
resistor. Signals labeled “TESTHI” should be pulled up to V
CC3
with a 10K
resistor. Signals labeled “GTLHI” should be pulled up to V
TT with a 10K resistor. All RESERVED
and NC pins must remain unconnected.
1.2
Signal Groups
In order to simplify the following discussion, signals have been combined into groups of like characteristics in
Table 1. See Section 3.0 in Chapter 2 and Chapter 3 for a description of the signals and their functions. All pins
of the Intel 450GX PCIset are listed here. Not all of these signals are available on the Intel 450KX PCIset. The
following pins do not exist on the Intel 450KX PCIset: CASA[7:4]#, CASB[7:4]#, DEP#[7:0], I2D[17:0],
I3D[17:0], IOGNT#, IOREQ#, OMCNUM, RASA[7:4]#, RASB[7:4]#, SYSERR#.
Table 1. Signal Groups
Pin Group
Signals
Notes
GTL+ Input
A[35:3]#, ADS#, AP[1:0]#, REQ[4:0]#, RP#, RESET#
(1)
GTL+ Output
BREQ0#
GTL+ I/O
A[35:3]#, ADS#, AERR#, AP[1:0]#, BERR#, BINIT#, BNR#, BPRI#,
D[63:0]#, DBSY#, DEFER#, DEP[7:0]#, DRDY#, HIT#, HITM#,
LOCK#,
REQ[4:0]#, RESET#, RP#, RS[2:0]#, RSP#, TRDY#
(1)
CMOS Input, 5V Tolerant
IOGNT#, FLSHBF#, MEMREQ#, PCLKIN, PGNT#, RECVEN
CMOS Input, 3.3V
BCLK, MDRDY[1:0]#, MEMCMD[7:0]#, MEMERR[1:0]#,
MIRST#,
OMCNUM, PWRGD, SYSCMD[4:0]#, SYSDEN#, TCK, TDI, TMS,
TRST#
CMOS Output, 6mA, 5V Tolerant FLUSH#, INIT#, PCIRST#, SMIACT#
CMOS Output, 6mA, 3.3V
MEMERR[1:0]#, SYSCMD[4:0]#, SYSERR#, TDO