Channel Link Evaluation Kit User Manual
National Semiconductor Corporation
Interface Products
LIT# CLINK3V28BT-85-UM
Rev 2.1
Date: 10/12/2005
Page 5 of 28
How to set up the Evaluation Kit:
The PCB routing for the Tx input pins (TxIN) have been laid out to accept incoming
data from a 60-pin IDC connector. The TxOUT/RxIN interface uses the 3M MDR
connector and Spectra Strip cable. This typical cable provides minimal skew
between LVDS channels and can typically support longer lengths than atwisted pair
cable. Please follow these steps to set up the evaluation kit for bench testing and
performance measurements:
1) Connect one end of the Spectra Strip cable to the transmitter board and the other
end to the receiver board. This is a standard pinout cable, longer lengths are
available for purchase from Alliance Technology – see www.alliancet.com
2) Jumpers have been configured at the factory, they should not require any
changes for operation of the chipset. See text on Jumper settings for more
details.
3) For the incoming data, connect a flat (ribbon) cable to the transmitter board to a
data source (signal generator, pattern generator, BERT tester, etc). Connect the
60-pin flat cable from the receiver board to the receiver load (BERT or other
equipment). Scope probes may also be connected directly to the pins if desired.
Mini-coax cable with headers on one end may also be used. This type of cable is
supplied with some test equipment. The 60-pin IDC equipment interface cable is
supplied with this kit which can be used to build custom cables.
4) Power for the Tx and Rx boards must be supplied externally through TP1 (Vcc).
Grounds for both boards are connected through TP2 (GND) (see section below).
5) Data applied to the inputs is now serialized, transmitted, deserialized and re-
driven at the receiver outputs.
This evaluation kit can also be used to evaluate the performance of other National
Semiconductor’s 28-bit and 21-bit Channel Link Serdes chipset. Simply replace the
existing DS90CR287/288A devices with a different 28-bit or 21-bit device chipset
and follow the above procedure. For evaluation of 21-bit device chipset, user needs
to pull TxIN[21:27] high or low.
Power Connection:
The Transmitter and Receiver boards must be powered by supplying power
externally through TP1 (Vcc) and TP2 (GND) on EACH board. Information on
maximum supply voltage can be found on device datasheet’s Absolute Maximum
Ratings section. The maximum voltage that should ever be applied to the Channel
Link Transmitter (DS90CR287) or Receiver (DS90CR288A) Vcc terminal is +4V
MAXIMUM.
