Does the Isolator affect signal quality?

The 7054-based USB Hi-Speed Isolator is a phy-level receiver/isolator/reclocker/repacketizer working at a bidirectional bandwidth of 480 MBit/s.
It receives and transmits USB data using a dedicated ULPI-transceiver, buffers and translates by our proprietary logic using FPGA technology and isolates using industry-leading RF-type isolators by Silicon Labs with least possible capacitance.
It does not translate or distort data packets like a hub but does reproduce and reclock the original data by 100%.

The circuit is a 50 ohms impedance controlled design. USB traces are matched to 90 ohms differential / 30 ohms single ended. The RMS jitter of the isolated downstream has been measured at 12.5ps.

By using a technology well known in digital communication systems called Spread Spectrum, any harmonics produced through periodic packet transmission (like 8kHz packet noise) could be eliminated.

The isolated side is supplied by our own proprietary and very careful designed DC/DC converter followed by linear regulators. The USB output voltage is generated by the Analog Devices ADP125 linear regulator.