OCX160 Datasheet, PDF (40/44 Pages) List of Unclassifed Manufacturers – OCX160 Crosspoint Switch

OCX160 Crosspoint Switch—Preliminary Data Sheet
6. Power Consumption
There are two main factors to consider when calculating power consumption for the OCX160:
• Power consumed by the chip
• Power dissipated by the terminating resistors at the switch differential outputs
The first component, chip power, consists of three integral elements (refer to Figure 22):
1. Input Power—This element is fixed (always ON) due to the DC current for differential outputs.
2. Core Power—This element is the same for LVDS or LVPECL outputs. Core power is a function of
data rate (Mb/s) and the number of connection paths through the switch matrix.
3. Ouput Power—This element is a fixed amount for each differential output. The value is zero if the
Output Enable (OE#) is disabled or set to OFF.
The second component, termination power, is the power dissipated by the terminating resistors at the
switch differential outputs. The value is zero if the Output Enable (OE#) is disabled or set to OFF.
The following diagram shows the chip power elements (as described above), the formulas used for
determining chip power, and the total power consumption as determined by the formula [Chip Power +
Termination Power].
6.1 Power for LVDS I/O
Chip Power
+
Termination Power
Input
Power
(always ON)
Core
Power
Switch
Matrix
Output
Power
Output
Buffer
CLK
Termination
Power
R_S
R_DIV
R_S
4mW/Input ₊ 0.015mW/Mbs/Connection + 4mW/Output ₊ 16mW/Output (Load)
Chip Power
Termination Power
Example: Worst Case = (4mW x 80) + (0.015 mW x 667 x 80) + (4mW x 80) + (16mW x 80)
320mW ₊ 800mW
+ ^320mW + ^1280mW
= 1440mW ₊ 1280mW
= 2.72 watts (total power consumption)
Figure 22 Power Consumption Diagram for the OCX160 using LVDS
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[Rev. 1.6] 2/20/01
I-Cube, Inc.