Programmable Devices
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How to use LVDS?

Altera_Forum
Honored Contributor II
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in datasheet,i find maybe it isn't similar to use LVDS in Cyclone1,cyclone2,and cyclone3, 

so what can i do if i want to use LVDS? 

1,does it need resistor? 

2,how many wire i need ? 

in my opinion there is two way to do this 

the one is two wire and use CDR, 

and the other is four wire use two to send data ,and two as clock reference. 

can you tell me the trues? 

thank u
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Altera_Forum
Honored Contributor II
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See figure 8-2 in this document on Altera's web site. It shows how to implement true LVDS with Cyclone III. http://www.altera.com/literature/hb/cyc3/cyc3_ciii51008.pdf

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Altera_Forum
Honored Contributor II
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The maximum voltage output differential (VOD) is increased to 600mV. The maximum VOD for ANSI specification is 450mV. 

The input voltage range can be reduced to the range of 1.0V to 1.6V, 0.5V to 1.85V or 0V to 1.8V based on different frequency ranges. The ANSI/TIA/EIA-644 specification supports an input voltage range of 0V to 2.4V. 

 

-------------------------------------------------------------------------------- 

 

As above is the CIII's DC/AC Spec. 

I want to ask a question: 

If I use CIII's a receiver, it can support these Voltage? VIH=0.85V, VIL=0.5V, VID=300mV. 

 

thanks, 

tony
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Altera_Forum
Honored Contributor II
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i am learn lvds too , thanks your post

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