Stratix® V Device Handbook: Volume 1: Device Interfaces and Integration

ID 683665
Date 10/18/2023
Document Table of Contents Emulated LVDS, RSDS, and Mini-LVDS Termination

The I/O banks also support emulated LVDS, RSDS, and mini-LVDS I/O standards.

Emulated LVDS, RSDS and mini-LVDS output buffers use two single-ended output buffers with an external three-resistor network, and can be tri-stated.

Figure 107. Emulated LVDS, RSDS, or Mini-LVDS I/O Standard TerminationThe output buffers, as shown in this figure, are available in all I/O banks. For LVDS output with a three-resistor network, RS is 120 Ω and RP is 170 Ω. For RSDS and Mini-LVDS output, RS and RP values are pending characterization.

To meet the RSDS or mini-LVDS specifications, you require a resistor network to attenuate the output-voltage swing.

You can modify the three-resistor network values to reduce power or improve the noise margin. Choose resistor values that satisfy the following equation.

Figure 108. Resistor Network Calculation

Note: Altera recommends that you perform additional simulations with IBIS or SPICE models to validate that the custom resistor values meet the RSDS or mini-LVDS I/O standard requirements.

For information about the data rates supported for external three-resistor network, refer to the device datasheet.