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Altera_Forum
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11 years ago

LVDS problems (Cyclone IV)

Is there any problem with using direct LVDS connections between two Altera devices (Cyclone IV) residing on different boards (without external transceivers)?

We are facing strange behavior that is reflected by low impedance (few ohms) between the LVDS signal (usually the negative line) and GND. The relevant signals are sometimes unstable and sometimes not functional at all.

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  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    Ideally there should not be issue interfacing since both are same device family and with similar LVDS IO standard. Have you had a chance to check on the electrical values ie VOD, VID, VCM at the TX and RX of both devices to see if still within the specs?