Specifications

PENTIUM® PRO PROCESSOR AT 150, 166, 180, and 200 MHz E
52
V
IN_LOW_MAX
= V
REF
- 200 mV at the rate of
0.3V/ns.
4. For both the 0.3 V/ns edge rate and faster edge
rates (up to 0.8 V/ns for Lo-to-Hi, and 3 V/ns for
Hi-to-Lo —dashed lines in Figure 34 and
Figure 35), one must ensure that lower starting
voltages of the input swing (V
START
in the range
‘V
REF
−200 mV’ to 0.5 V for Lo-to-Hi transitions,
and 1.5 V to ‘V
REF
+200 mV’ for Hi-to-Lo
transitions —dashed lines in Figure 34 and
Figure 35) do not require T
SU
to be made
longer. This step is needed since a lower
starting voltage may cause the input differential
amplifier to require more time to switch, due to
having been in deeper saturation in the initial
state.
Time
V
REF
V
REF
+ 0.2
V
REF
− 0.2
0
.3 V
/ns
V
start
1
.5 V
/ns
1.5 V Clk Ref
Clock
T
su
Figure 34. Standard Input Lo-to-Hi Waveform for Characterizing Receiver Setup Time