Finalizing the schematics of our ULPI transceiver

A project log for CyL3D

Rethinking POV : what about 3D?

AlexisAlexis 06/13/2021 at 18:080 Comments

By Paul:

Last friday we had a class about signal integrity. As we learnt about all the problems we could have, I finally understood the use of all the bypass capacitors and some of the other esoteric symbols or annotation that are no longer a mystery (such as 0-ohm resistors or DNI annotations)

Thus, I had to update the schematic of the ULPI/USB subsystem of our project.  You can see it below. Here are some important changes :

ULPI/USB Subsystem Schematic

As such, our ULPI/USB system should work. However, I have a doubt about whether or not I should add a resistor on the wire between the oscillator’s CLK and the USB3320C REFCLK. Our development kit has a resistor on its schematic, but the oscillator’s datasheet does not mention to put a resistor on the CLK output. If anybody has an idea about it, I’d be happy to hear it.