5. Electrical Characteristics
201
Tsi308 User Manual
80D4000_MA001_02
Tundra Semiconductor Corporation
www.tundra.com
5.7
HyperTransport Impedance Requirements
R
TT
is the value of the differential input impedance of the receiver under DC conditions
implemented with an on-die differential terminating resistor. This specification must be
supported by any compensation technique used within the receiver across all device specific
process, voltage, and temperature operating points. The R
TT
value is defined to match the Z
OD
of the coupled transmission lines and to provide a slightly overdamped single-ended
termination.
R
ON
is the driver output impedance under DC conditions. This range must be maintained over
the valid V
OD
range. This specification must be supported by any compensation technique used
within the output driver across all device specific process, voltage, and temperature operating
points. The R
ON
value is defined to match one-half of the Z
OD
of the coupled transmission lines.
DR
ON
(pull-up) is the allowable difference in the driver output impedance between the true and
complement when driving a logic ë0í and when driving a logic ë1í (additionally defined as when
true is driven high and when complement is driven high). DR
ON
(pull-up) is defined to limit
differences in both output rising edge slew rate and the resulting differential skew and crossing
point shift.
DR
ON
(pull-down) is the allowable difference in the driver output impedance between the true
and complement when driving a logic ë1í and when driving a logic ë0í (additionally defined as
when true is driven low and when complement is driven low). DR
ON
(pull-down) is defined to
limit the differences in both output falling-edge slew rate and the resulting differential skew and
crossing point shift.
The following table gives the DC specifications for these parameters.
Table 27: R
TT
and R
ON
DC Specifications
Parameter
Description
Min
Typ
Max
Units
R
TT
Differential Termination
90
100
110
W
R
ON
Driver Output Impedance
45
50
55
W
R
ON
(pull-up)
High-Drive Impedance Magnitude Change
0
-
5
%
R
ON
(pull-down)
Low-Drive Impedance Magnitude Change
0
-
5
%
Summary of Contents for TSI308
Page 4: ...4 Tsi308 User Manual 80D4000_MA001_02 Tundra Semiconductor Corporation www tundra com ...
Page 6: ...6 Tsi308 User Manual 80D4000_MA001_02 Tundra Semiconductor Corporation www tundra com ...
Page 20: ...20 Tsi308 User Manual 80D4000_MA001_02 Tundra Semiconductor Corporation www tundra com ...
Page 260: ...Index 260 Tsi308 User Manual 80D4000_MA001_02 Tundra Semiconductor Corporation www tundra com ...