AMD ATHLON 8 - Manual (Page 50)

38 Electrical Data Chapter 8
AMD Athlon™ XP Processor Model 8 Data Sheet 25175H—March 2003
Preliminary Information
8.10 AMD Athlon™ System Bus DC Characteristics
Table 15 shows the DC characteristics of the AMD Athlon
system bus used by the AMD Athlon XP processor model 8.
Table 15. AMD Athlon™ System Bus DC Characteristics
Symbol Parameter Condition Min Max Units Notes
V
REF
DC Input Reference Voltage
(0.5 x V
CC_CORE
)
–50
(0.5 x V
CC_CORE
)
+50
mV 1
I
VREF_LEAK_P
V
REF
Tristate Leakage Pullup V
IN
= V
REF
Nominal –100
µA
I
VREF_LEAK_N
V
REF
Tristate Leakage Pulldown V
IN
= V
REF
Nominal 100
µA
V
IH
Input High Voltage V
REF
+ 200 V
CC_CORE
+ 500 mV
V
IL
Input Low Voltage –500 V
REF
– 200 mV
I
LEAK_P
Tristate Leakage Pullup
V
IN
= VSS
(Ground)
–1 mA
I
LEAK_N
Tristate Leakage Pulldown
V
IN
= V
CC_CORE
Nominal
1 mA
C
IN
Input Pin Capacitance 4 7 pF
R
ON
Output Resistance 0.90 x R
setN,P
1.1 x R
setN,P
Ω
2
R
setP
Impedance Set Point, P Channel 40 70
Ω
2
R
setN
Impedance Set Point, N Channel 40 70
Ω
2
Notes:
1. V
REF
is nominally set to 50% of V
CC_CORE
with actual values that are specific to motherboard design implementation. V
REF
must be
created with a sufficiently accurate DC source and a sufficiently quiet AC response to adhere to the ± 50 mV specification listed
above.
2. Measured at V
CC_CORE
/ 2.