EP80579 Datasheet, PDF (1863/1916 Pages) Intel Corporation – Intel® EP80579 Integrated Processor Product Line

Intel^® EP80579 Integrated Processor
49.5.6
System Management Bus (SMBus)
The SMBus is SMBus 2.0 compliant and is also compatible with most 2-wire
components that are I²C compatible. The host interface allows the EP80579 to
communicate via SMBus, the slave interface allows external microcontrollers to access
system resource in the IICH. The SMB does not support access to internal configuration
registers. Access to the external DIMMs is through the IICH, via I²C. This is used to
determine the nature of the DIMMs present in order to configure the memory
subsystem correctly, including the configuration of the D-unit.
This section describes the electrical characteristics of the System Management Bus
(SMBus) interface.
49.5.6.1
SMBus Signal List
For SMBus pin description refer to Table 48-15, “SMBus Interface Signals” on
page 1750.
49.5.6.2 SMBus DC Characteristics
Table 49-36. SMBus DC Input Characteristics
Symbol
Parameter
Conditions
Min Typical Max
Units
Notes
V_IH
Input voltage high
-
2.0
-
-
V
2
V_IL
Input voltage low
-
-
-
0.8
V
2
Ι_leak
Input Leakage
Current
0<V_IN<Vcc3_3
-
-
±5
µA
-
C_IN
Input-pin
capacitance
-
-
-
10
pf
1
1.
2.
VIH and VIL for Intruder# is guaranteed by design. These values are typical values seen for this process, but
not measured during production testing.
Table 49-37. SMBus DC Output Characteristics
Symbol
Parameter
Conditions
Min
Typical
Max
Units
Notes
V_OL
Output voltage low
lout=4mA
0.4
V
1,2
Notes:
1.
VOH spec does not apply to signals that are open drain driver. Open drain signals must have an
external pull up resistor.
2.
VOL for Intruder# is guaranteed by design. These values are typical values seen for this process, but not
measured during production testing.
Table 49-38. SMBus DC Clock Specification (Sheet 1 of 2)
Symbol
Parameter
Conditions
Min
Typical
Max
Units
Notes
V_IH
Input voltage high
2.1
-
3.63
V
-
V_IL
Input voltage low
-
0.8
V
-
Notes:
1.
Guaranteed by design. These values are typical values seen for this process, but not measured
during production testing.
August 2009
Order Number: 320066-003US
Intel^® EP80579 Integrated Processor Product Line Datasheet
1863