I want to measure LVDS signals with a scope.

Will my solution work? (shown at bottom)

I know of other ways of doing this. But I am hoping this way is cleaner and easier.

Specs:

• Frequency:~100MHz
• Load:100Ω differential

Required:

• Measure DC-COUPLED signal levels (in reference to GND). cannot be inferred, must be measured with decent accuracy. This solution won't cut it: How to connect LVDS signals to oscilloscope?
• Measure differential amplitude (Q-*Q)
• Measure common-mode level (mean(Q+*Q))

Preferred:

• Avoid differential probes
• Use standard BNC or SMA terminating to 50Ω

I am using a Ferrite-Bead to reference the SCOPE-GND to PCB-GND (for measuring DC levels). The bead blocks AC currents terminating to PCB-GND... Insuring I(Q)=I(*Q)∙(-1).

I want to measure LVDS signals with a scope.

Will my solution work? (Shown at bottom.)

I know of other ways of doing this, but I am hoping this way is cleaner and easier.

Specs:

• Frequency:~100MHz
• Load:100Ω differential

Required:

• Measure DC-coupled signal levels (in reference to GND.) This cannot be inferred, it must be measured with decent accuracy. This solution won't cut it: How to connect LVDS signals to oscilloscope?
• Measure differential amplitude (Q-*Q)
• Measure common-mode level (mean(Q+*Q))

Preferred:

• Avoid differential probes
• Use standard BNC or SMA terminating to 50Ω

I am using a ferrite bead to reference the SCOPE-GND to PCB-GND (for measuring DC levels). The bead blocks AC currents terminating to PCB-GND, insuring I(Q)=I(*Q)∙(-1).