The ML4022-LB SFP-DD Passive Electrical Loopback is used for testing SFP-DD transceiver ports under board level tests. . By substituting a full-featured SFP-DD transceiver with the ML4022-LB, its electrical loopback provides a cost effective low loss method for SFP-DD port testing.
The ML4022-LB is packaged in a standard MSA housing compatible with all SFP ports. High speed signals are electrically looped back from TX side to RX side of the module, the differential TX pair is connected to the corresponding RX pair, and the signals are AC coupled as specified by SFP-DD MSA HW specs.