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AR# 22420

Spartan-II/-IIE/-3/-3L/-3E - What is the default I/O standard?

Description

If I do not specify an I/O standard constraint on user I/Os, which I/O standard will be used?

Solution

Single-ended standard:

- For Spartan-II and Spartan-IIE devices, the default I/O standard is LVTTL, 12 mA, slow slew rate.

- For Spartan-3/-3L/-3E devices, the default I/O standard is LVCMOS 2.5V, 12 mA, slow slew rate.

Differential I/O standard:

- Spartan-II devices do not support the differential I/O standard.

- To instantiate the differential I/O standard in Spartan-IIE devices, refer to the data sheet at: http://www.xilinx.com/support/documentation/data_sheets/ds077.pdf
- For Spartan-IIE devices, the default differential I/O standard is LVDS 3.3V.

- For Spartan-3/-3L/-3E series devices, the default differential I/O standard is LVDS 2.5V.

AR# 22420
Date Created 09/04/2007
Last Updated 12/15/2012
Status Active
Type General Article