SN55LVDS31-SP: VIH for 1.8V interface

Hi David,

Thank you for your question. The input high for this device is 2-V, so a 1.8-V input would not meet the requirements. 

You are likely looking for a 1.8-V space-grade LVDS driver, which we currently do not have in our portfolio.

A level shifter is an option. Here is a helpful guide for level shifters: Logic Guide (Rev. AB) (ti.com)

And a helpful application note to guide you in implementation: How to Support 1.8-V Signals Using a 3.3-V LVDS Driver/Receiver + Level-Shifter (ti.com)

I have filtered through -SEP and -EP level shifting options here: Direction-controlled voltage translators product selection

The input requirement to the SN55LVDS31-SP is LVTTL, meaning that the VIN minimum requirement is 2.0-V (see page 4 on the Logic Guide). The output of the level-shifter must meet this requirement. 

Feel free to reach to the logic & voltage translation team to see if they have any space-grade recommendations. 

Hope this helps! -Amy