Electrical Specifications (Continued)
7.6 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 7-6. Input or output signals must cross
these levels during testing.
All AC tests are at VCC2 = 2.75V to 3.05V (2.9V nominal),
TC = 0oC to 70oC or 85o, CL = 50 pF unless otherwise
specified.
Table 7-6. Drive Level and Measurement Points
for Switching Characteristics
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.
Symbol
Voltage (V)
VREF
VIHD
VILD
1.5
2.4
0.4
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 7-1. Drive Level and Measurement Points for Switching Characteristics
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