Electrical Specifications (Continued)
6.7 AC CHARACTERISTICS
The following tables list the AC characteristics including
output delays, input setup requirements, input hold
requirements, and output float delays. The rising-clock-
edge reference level VREF, and other reference levels are
shown in Table 6-13. Input or output signals must cross
these levels during testing.
While most minimum, maximum, and typical AC charac-
teristics are only shown as a single value, they are tested
and guaranteed across the entire processor core voltage
range of 2.2V to 2.9V (nominal). AC characteristics that
are affected significantly by the core voltage or speed
grade are documented accordingly.
Input setup and hold times are specified minimums that
define the smallest acceptable sampling window for which
a synchronous input signal must be stable for correct oper-
ation.
Table 6-13. Drive Level and Measurement
Points for Switching Characteristics
Symbol
Voltage (V)
All AC tests are performed at VCC2 = 2.1V to 2.31V (2.2V
VREF
VIHD
VILD
1.5
2.4
0.4
Nominal), VCC2 = 2.37V to 2.63V (2.5V Nominal), VCC2
=
2.76V to 3.05V (2.9V Nominal), VCC3 = 3.0V to 3.6V (3.3V
Nominal), TC = 0oC to 85oC, RL = 50 ohms, and CL = 50
pF unless otherwise specified
T
X
V
IHD
V
REF
CLK
V
ILD
A
Max
B
Min
Valid Output
Valid Output
V
OUTPUTS
n+1
n
REF
C
D
V
V
IHD
V
Valid Input
REF
INPUTS
ILD
Legend: A = Maximum Output Delay Specification
B = Minimum Output Delay Specification
C = Minimum Input Setup Specification
D = Minimum Input Hold Specification
Figure 6-4. Drive Level and Measurement Points for Switching Characteristics
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