MOTOROLA M68020 USER’S MANUAL 10-7
AC ELECTRICAL CHARACTERISTICS—CLOCK INPUT (see Figure 10-2)
16.67 MHz 20 MHz 25 MHz* 33.33 MHz
Num. Characteristic Min Max Min Max Min Max Min Max Unit
Frequency of Operation 8 16.67 12.5 20 12.5 25 12.5 33.33 MHz
1 Cycle Time 60 125 50 80 40 80 30 80 ns
2,3 Clock Pulse Width
(Measured from 1.5 V to 1.5 V)
24 95 20 54 19 61 14 66 ns
4,5 Clock Rise and Fall Times — 5 — 5 — 4 — 3 ns
*These specifications represent an improvement over previously published specifications for the 25-MHz MC68020 and
are valid only for products bearing date codes of 8827 and later.
Figure 10-2. Clock Input Timing Diagram