AMD Geode™ LX Processors Data Book 607
Electrical Specifications 33234H
7.6 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 VREF
, and other reference levels are shown in
Figure 7 -2. Inp ut 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 the following parameters
using the timing diagram shown in Figure 7-2 unless other-
wise specified:
VCORE: 1.14V to 1.26V (1.2V Nominal)
VIO: 3.14V to 3.46V (3.3V Nominal)
VMEM: 2.5V SSTL
MVREF:DDR:1.25V
TC:0
oC to 85oC
RL:50 Ω
CL:50 pF
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 1.14V to 1.26V. AC characteristics that are affected sig-
nificantly by the core voltage or speed grade are docu-
mented accordingly.
All AC timing measurements are taken at 50% crossing
points for both input times and output times.

Figure 7-2. Drive Level and Measurement Points for Switching Characteristics

CLK
Outputs
Inputs
VIHD
VILD
VREF
Valid Input
Valid Output n+1
Valid Output n
VREF
VREF
VILD
VIHD
Min
Max
Legend: A = Maximum Output or Float Delay Specification
B = Minimum Output or Float Delay Specification
C = Minimum Input Setup Specification
D = Minimum Input Hold Specification
TX
B
A
CD