Intel Embedded Intel486 Hardware Reference Manual page 316

EMBEDDED Intel486™ PROCESSOR HARDWARE REFERENCE MANUAL
optimized by using proper terminations and by keeping the length of the traces as short as possi-
ble. The preferred method is to connect all of the loads via a single trace as shown in
thus avoiding the extra stubs associated with each load. The loads should be as close to one an-
other as possible. Multiple clock sources should be used for distributed loads.
Clock
Source
A less desirable method is the star connection layout in which the clock traces branch to the load
as closely as possible (Figure
The maximum allowable length of the traces depends upon the frequency and the total fanout, but
the length of all of the traces in the star connection should be equal. Lengths of less than one inch
are recommended.
Clock
Source
10-32
Load 1 Load 2
Figure 10-25. Clock Routing
10-26). In this layout, the stubs should be kept as short as possible.
Series
Termination
Figure 10-26. Star Connection
Load 3
Load 3
Figure 10-25,
Thevenin's
Termination
Load 1
Load 2