National Semiconductor DS15BA101 User manual

January 2008
Rev. 0.3
150 – 1500 Mbps Cable Extender
Chipset
(DS15BA101/DS15EA101)
Evaluation Kit
USER MANUAL
Part Number: DriveCable02EVK NOPB
For the latest documents concerning these products and evaluation kit, visit lvds.national.com. Schematics
and gerber files are also available at lvds.national.com.

DriveCable02EVK User Manual
Table of Contents
Overview................................................................................................................................................ 3
Board Description................................................................................................................................... 4
Setting Up the DriveCable02EVK Evaluation Kit ................................................................................. 5
Evaluation with the 100-ohm Differential Balanced Cables .................................................................. 6
Evaluation with the 50-ohm Coaxial Cables ........................................................................................ 10
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DriveCable02EVK User Manual
Overview
The DriveCable02EVK is an evaluation kit designed for demonstrating performance of the DS15BA101
and DS15EA101, a cable extender chipset. The kit enables evaluation of the chipset with 100-ohm
differential cables such as twin-axial and low cost CAT5e/6/7 twisted pair cables and 50-ohm coaxial
cables.
The purpose of this document is to: familiarize you with the DriveCable02EVK, suggest the test setup
procedures and instrumentation, and guide you through some typical measurements that demonstrate
performance of the chipset in typical applications.
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DriveCable02EVK User Manual
Board Description
Figure 1 shows a drawing of the board. It is a 3 inch x 4 inch 6-layer PCB with a two-device layout that is
capable of demonstrating performance and all features of the DS15BA101 and DS15EA101.
VDD
Vbias
GND
Figure 1. DriveCable02EVK Board
Connector Device Function
JP1 U1 Select output amplitude
JP2 U2 Output enable
JP3 U1 Set input common mode
voltage (Optional)
Table 1. DriveCable02EVK Connector-Device-Function Cross Reference
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DriveCable02EVK User Manual
Setting Up the DriveCable02EVK
Evaluation Kit
This section provides a quick reference for setting up some typical test configurations using the
DriveCable02EVK that will enable you to evaluate the solution with 100-ohm differential cables (twin-
axial and twisted pair cables) as well as 50-ohm coaxial cables.
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DriveCable02EVK User Manual
Evaluation with 100-ohm Differential Balanced Cables
The DriveCable02EVK can be used to evaluate the chipset with 100-ohm differential cables (twin-axial
and twisted pair cables). Examples are CAT5e/6/7 cable assemblies such as Belden 1500A, Belden 1700A,
Siemon CAT7 Tera, Belden 89207 and Amphenol SKEWCLEAR series of cables. Figure 2 is a simplified
block diagram of the configuration.
Advantest D3186
Pattern Generator
Connector
Adapter
Connector
Adapter
Cable
Tektronix
TDS 6154C
Oscilloscope
Cable Extender Chipset Evaluation Board
P/N: DriveCable02EVK, Rev. 2.0
Gigabits@ManyMeters
U1
U2
Figure 2. Test Setup for 100-ohm Differential Cable Evaluation
Note: Connector Adapters are NOT included in this kit. Currently, RJ45-SMA adapters are
available and can be ordered separately. The part number is DS91C176EVK NOPB. If cable
assemblies have other than RJ-45 connectors, it is recommended to obtain/develop an adapter board
similar to the RJ45-SMA adapter to ensure good impedance control of the signal path. For more
information about the RJ45-SMA Adapter check:
http://www.national.com/appinfo/lvds/ds91c176evk.html
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DriveCable02EVK User Manual
Follow these steps to set up the DriveCable02EVK for evaluation with 100-ohm differential balanced
cables:
1. Configure DriveCable02EVK board:
a) Provide 3.3 V between the J2 (VDD) and J1 (GND). This powers all devices on the board.
b) Set DS15BA101 (U1) output voltage amplitude to 0.4 V by using JP1.
c) Enable DS15EA101 (U2) outputs by setting its EN* pin to low. This is accomplished by
placing a jumper across the GND and SIG pins of the connector JP2.
2. Connect the DS15BA101 inputs to a signal source (e.g. Pattern Generator or Serializer output).
a) Note the AC-coupling capacitors on the inputs (SMA1 and SMA2)
b) Adjust the signal parameters (VOH, VOL, VCM) so that they comply with the DS15BA101
input requirements.
c) If DC-coupled interface is desired, use 0-ohm SM0402 resistors in place of the C1 and C2.
d) There is a provision to add an optional resistor divider network (R12 and R13) on the
DS15BA101 inputs in case one desires biasing the input signal externally (note: there is
already an internal biasing network on the DS15BA101 inputs). In addition, the JP3
connector provides signal biasing provision for a voltage source.
3. Attach the connector adapters (if available) to the DS15BA101 outputs (SMA3 and SMA4) and
DS15EA101 inputs (SMA5 and SMA6).
4. Connect a 100-ohm cable assembly with corresponding plugs on its ends.
5. The LED1 will illuminate if the DS15EA101 (U2) detects a valid signal.
6. Connect the DS15EA101 (U2) outputs directly to an oscilloscope, a bit error rate tester (BERT)
receiver or a deserializer using good quality coaxial cables. Note that the equalizer outputs have
internal 50-ohm pull-ups and that there are on-board AC-coupling capacitors.
7. Observe the results on the oscilloscope or BERT receiver.
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DriveCable02EVK User Manual
Figure 3 presents typical maximum data rate as a function of CAT5e cable length. The data was
collected on four chipsets (A, B, C and D). The data in red was taken with the 0.5 UI jitter criteria
while the data in blue was taken with the 0.25 UI jitter criteria.
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
0 25 50 75 100 125
Cable Length [m]
Maximum Data Rate [Gbps]
A B C D A B C D
Figure 3. DS15BA101 and DS15EA101 Performance with CAT5e Cable
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DriveCable02EVK User Manual
Figure 4 presents maximum data rate as a function of CAT7 cable length. The data was collected on four
chipsets (A, B, C and D). The data in red was taken with the 0.5 UI jitter criteria while the data in blue was
taken with the 0.25 UI jitter criteria.
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
3.00
0 25 50 75 100
Cable Length [m]
Maximum Data Rate [Gbps]
A B C D A B C D
Figure 4. DS15BA101 and DS15EA101 Performance with CAT7 Cable
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DriveCable02EVK User Manual
Evaluating 50-ohm Coaxial Cables
The DriveCable02EVK can be used to evaluate 50-ohm coaxial cables. Examples of 50-ohm coaxial
cables are Belden 9914 and Andrew FSJ-50B. Figure 5 is a simplified block diagram of the configuration.
Advantest D3186
Pattern Generator
Cable
Tektronix
TDS 6154C
Oscilloscope
Cable Extender Chipset Evaluation Board
P/N: DriveCable02EVK, Rev. 2.0
Gigabits@ManyMeters
U1
U2
Figure 5. Test Setup for 50-ohm Coaxial Cable Evaluation
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