GX1 Datasheet, PDF (197/247 Pages) National Semiconductor (TI) – Processor Series Low Power Integrated x86 Solution

Electrical Specifications (Continued)
6.7 AC CHARACTERISTICS
The following tables list the AC characteristics including
output delays, input setup requirements, input hold require-
ments, and output float delays. The rising-clock-edge refer-
ence level V_REF, and other reference levels are shown in
Table 6-13. Input or output signals must cross these levels dur-
ing testing.
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 opera-
tion.
All AC tests are performed at V_CC2 = 1.52V to 1.68V (1.6V
Nominal), V_CC2 = 1.71V to 1.89V (1.8V Nominal), V_CC2 =
1.9V to 2.1V (2.0V Nominal), V_CC3 = 3.0V to 3.6V (3.3V
Nominal), T_C = 0^oC to 85^oC, R_L = 50 ohms, and C_L = 50 pF
unless otherwise specified
While most minimum, maximum, and typical AC character-
istics are only shown as a single value, they are tested and
guaranteed across the entire processor core voltage range
of 1.6V to 2.0V (nominal). AC characteristics that are
affected significantly by the core voltage or speed grade
are documented accordingly.
Table 6-13. Drive Level and Measurement Points
for Switching Characteristics
Symbol
Voltage (V)
V_REF
1.5
V_IHD
2.4
V_ILD
0.4
T_X
CLK
OUTPUTS
V_IHD
V_ILD
A
B _Min
Valid Output _n
Max
Valid Output _n+1
INPUTS
V_IHD
V_ILD
C
D
Valid Input
V_REF
V_REF
V_REF
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
Revision 1.0
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