Point-To-Point Connections - Analog Devices ADSP-2106x SHARC User Manual

ACTQ240 Octal Inverter
(National Semiconductor)
or
IDT49FCT805/A
or
CY7C992
Clock
Buffer Drive Impedance = 10 Ω
A separate buffer and transmission line is needed for each group
of processors that are further than 4 inches from each other.
Figure 11.6 Recommended Clock Distribution Method (Source Termination)
11.5.3

Point-To-Point Connections

A series termination resistor may be added near the pin for point-to-
point connections. This is typically used for link port applications
when distances are greater than 6 inches. See Figure 11.7. For more
specific guidence on related issues, see the reference source in the
Recommended Reading section for suggestions on transmission line
termination and see the ADSP-2106x Data Sheet for output drivers' rise
and fall time data .
For link port operation at a 2X clock rate it is important to maintain
low skew between the data (LxDAT
operation at CLKIN=40 MHz, a skew of less than 1.25 ns is required.
Although the ADSP-2106x's serial ports may be operated at a slow
rate, the output drivers still have fast edge rates and may require
source termination for longer distances.
www.BDTIC.com/ADI
System Design
40 Ω
50 Ω Transmission Line
40 Ω
50 Ω Transmission Line
40 Ω
50 Ω Transmission Line
) and clock (LxCLK). For 2X
3-0
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ADSP-2106x
ADSP-2106x
ADSP-2106x
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