Up to 15V logic isolator

Hi Ryan,

Here is a simulation for the situation. As in diagram, VG1 is the desired input signal, VG2 is unwanted signal but it is connected to the negative side of VG1 positive. This simulation will provide what I want and the LM7171 is fast enough to do the job. From the Oscilloscope, the upper chart is the output of the LM7171 (about from 0V to 5V), Second chart is the VG2 signal, the Lower Chart is the VG1 signal. Any change in the VG2 will not change the output of the LM7171( Here they are in sync, but even not synch it will not have any change on the output as clearly the circuit imply). So this is working OK, but still like to get this as a digital signal not analog, to improve signal and reduce noise and distortion. Any alternative you have?

Forgot to tell: VG2 -1 to 24V and VG1 0 to 5V