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Altera_Forum
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14 years ago

LVDS receiver resistors

I'm currently developing on a DE2-115 together with an HSMC daughter card (TI's ADS58B18EVM through HSMC-ADC-bridge adapter). I need to use LVDS I/O standard for interfacing the cards, so I know I ha...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

Hi Lorenzo,

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I'm currently developing on a DE2-115 together with an HSMC daughter card (TI's ADS58B18EVM through HSMC-ADC-bridge adapter). I need to use LVDS I/O standard for interfacing the cards, so I know I have to install 100-ohm resistors close to the FPGA to get things working.

I've looked on the web for a DE2-115 BOM or layout to find resistors part number or at least physical dimensions, but I couldn't.

Where can I find the informations I need? Anyone can help?

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I just looked for the layout in the DE115 distribution, but they only have the schematic in there. Page 23 shows the termination resistors you need to load on the DE115.

Try and locate R55, R56, etc. The footprints are most likely 0402 (40 mils x 20 mils = 1 mm x 0.5 mm). If the pads on the resistor footprints are about the same distance apart as the BGA balls (or the vias on the bottom of the PCB ), then the resistors are 0402.

If you cannot figure it out, let me know, and I'll look on the board I have at home.

Cheers,

Dave