A simple SFP loopback board that loops back any received signal on the SFP RX-pins to the TX-pins. There's a voltage divider probing the signals, and an ONET1191P limiting amplifier provides amplified differential outputs, for probing the signal going through the SFP.
Designed in 2018, but only now uploaded to github, a simple SFP breakout board for playing around with SFP or SFP+ transcievers.
In contrast to earlier boards, this one has no op-amps or transformers on the TX/RX lines, and bandwidth seems to be good enough for 1Gbit/s at least.
20pin SMD connector + cage for SFP transceiver.
This is the fourth version of an interface board to Small Form Factor Pluggable optical transcievers (SFPs) with a bandwidth of >500 MHz. These are useful for various time/frequency experiments, with a measured frequency stability of <1e-13 @ 1s (in 0.5 or 5 Hz bandwidth) - perhaps slightly depending on what SFP is used. The SFP allows sending the signal along a single-mode fiber for 1-100 km easily.
ADT2-1T converts to and from differential signals while LMH6702 op-amps provide 3 dB gain. There are parallel outputs on the RX pins. The current-draw on +3V3 by the SFP is quite high - usually requiring heat-sinking on the voltage-regulator
KiCad files available on request.