10GHz Regime Differential to Single Ended Conversion

Question

I'm looking for a board mount (IC) solution that will take the differential output of something like ONET1191 @10GHz and convert it to 50 or even 75 Ohm single ended.

I've looked through various suppliers for:

• Baluns (and other transformer solutions)
• Differential Amplifiers
• Receivers/Transceivers

However, I can not seem to find any modules with a pass band around 10GHz. I see tons and tons of ~6GHz modules (makes sense because 1080p60).

Alternatively, I could simply pass it out through 100 Ohm twinax and into a discrete RF amp that takes differential input (those do exist, but they are expensive!!!). I am hoping to avoid this, due to cost reasons.

Just throwing this out into the wind to catch some useful suggestions, thanks!

Answer 1

The typical solution is just to terminate one half of the differential output and deliver the other half to the single-ended transmission line. Your device provides up to 700 mV peak-peak output, which is as high as you're likely to see in a logic buffer at this data rate.

If you need a buffer amplifier to maybe prevent damage to the more-expensive TIA chip due to being connected to an off-board circuit, you could look at something like On Semi's NBSG16 12 Gb/s buffer.

If you need more than 700 mV swing, you could look at something designed as an electro-optic modulator driver, for example Picosecond Pulse Labs (now Tektronix) 5865 amplifier. This can do up to 8 V peak-peak output at 12.5 Gb/s.