82551IT — Networking Silicon
11.3
AC Specifications
Table 54. AC Specifications for PCI Signaling
Symbol
Parameter
Condition
0 < VOUT 1.4
Min
Max
Units Notes
-44
mA
mA
mA
mA
mA
mA
mA
mA
1
1
2
2
1
1
2
2
Switching
1.4 < VOUT < 0.9VCC
0.7VCC < VOUT < VCC
VOUT = 0.7VCC
-17.1(VCC - VOUT)
Current High
IOH(AC)
Eqn A
(Test Point)
-32VCC
VOUT 2.2
95
Switching
2.2 > VOUT > 0.1VCC
0.18VCC > VOUT > 0
VOUT = 0.18VCC
VOUT/0.023
Current Low
IOL(AC)
Eqn B
38VCC
(Test Point)
Low Clamp
Current
ICL
-3 < VIN -1
-25 + (VIN + 1)/0.015
mA
mA
3
High Clamp
Current
25 + (VIN - VCC -1)/
0.015
ICH
VCC + 4 > VIN VCC + 1
0.4 V to 2.4 V
PCI Output Rise
Slew Rate
slewRP
slewFP
1
1
4
4
V/ns
V/ns
PCI Output Fall
Slew Rate
2.4 V to 0.4 V
NOTES:
1. Switching Current High specifications are not relevant to PME#, SERR#, or INTA#, which are open drain
outputs.
2. Maximum current requirements will be met as drivers pull beyond the first step voltage (AC drive point).
Equations defining these maximums (A and B) are provided. To facilitate component testing, a maximum
current test point is defined for each side of the output driver.
Equation A. IOH = (98/VCC)*(Vout - VCC)*(Vout + 0.4VCC), for VCC > Vout > 0.7VCC
Equation B. IOL = (256/VCC)*(Vout)*(VCC - Vout), for 0 < Vout < 0.18VCC
3. Do not test. Guaranteed by design.
80
Datasheet
INTEL [ INTEL ]
