I'm currently designing a 24-port USB 2.0 switching device/KVM and am evaluating the MAX4999 for the switching functionality. The datasheet describes how to connect two MAX4999 devices to create a 16:1 configuration.
I'm considering scaling this to a 24:1 setup using three MAX4999 chips. Based on my understanding, this should work - as long as only one chip is active at a time and the unused devices are properly disabled to avoid bus contention. If we go this route, we would focus on impedance control to minimize discontinuities caused by additional vias and crossover routing.
An alternative would be to use a 3:1 switch in front of three MAX4999s to isolate each path, but I’m concerned this approach may introduce additional signal integrity loss based on previous testing of multi-stage USB switching devices.
Can you confirm whether using three MAX4999 devices in this way (with only one active at a time) is a valid approach for 24:1 USB 2.0 switching, or would you recommend a different configuration?
