Electronic – way I can convert from USB to LVDS UART (~1Mbps)?


I'm working on a spacecraft that requires very low noise levels so it was requested that we pursue LVDS UART. So it's using something similar to RS-422 because it's differential, but instead of a signal that is 0-5V, it is a current loop that produces a differential signal that's about 300 mV.

My issue is that for testing purposes we need to be able to talk to that interface from a computer using USB. Normally we would use USB to TTL UART but that won't work for this situation. It would be nice if there was a USB to LVDS UART such that it presented a standard serial interface to the computer but used LVDS to connect to our board for testing. An FPGA on the board is handling the UART. The connection needs ~1 Mbps.

So far I've been looking for something like a USB-FTDI TTL cable but that would work with LVDS UART. So far I haven't found anything. Maybe someone with more knowledge than I can help me find a solution.

Edit I don't need product recommendations. When I mentioned looking for products I was merely trying to explain what I had been exploring in trying to find a solution. The core of my question is whether or not doing this was possible and if it was, what kind of solutions should I explore.

Best Answer

Typically an UART does not include a PHY, and thus any external PHY can be used for implementing the communication bus.

So feel free to select any suitable PHY for this, there are a lot of PHYs that implement low EMI by using a differential connection or limiting the slew rate. The PHYs include RS485, CAN, in addition to LVDS of course.