Hold Time; Flight Time (Falling Edge) - Intel Pentium II Application Note

Figure 7 shows the determination of flight time for the falling edge of a signal.
Figure 7. Flight Time (Falling Edge)
2.0 V
1.4 V
0.8 V
The flight time of the falling edge is determined between the driver and receiver at 1.4 V.
However, if the edge rate of the flight time is less than 1 V/ns, then the flight time is determined
between the driver at 1.4 V and the receiver at 0.8 V (V
The maximum flight time is the greater of the two measurements.
6.1.2

Hold Time

The minimum flight time measurement is used to determine the hold time of a memory signal.
The flight time of the rising edge is determined between the driver and receiver at 1.4 V.
However, if the edge rate of the flight time is less than 1 V/ns, then the flight time is determined
between the driver at 1.4 V and receiver at 0.8 V (V
The minimum flight time is the lesser of the two measurements.
Repeat the above process for the falling edge with the exception that the flight time is measured
between 1.4 V and 2.0 V.
Application Note
Low-Power Module Memory Bus Simulation Methodology
1 V/ns
), and derating it by adding 600 ps.
il
1 V/ns
), and derating it by subtracting 600 ps.
il
0.8 V
A6435-01
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