I'm working on a signal generator using a high speed DAC, which has balanced current outputs (two outputs, each 0-20mA, 180 degrees out of phase). The DAC is 250MSPS, so I'd like the analog frontend to handle up to about 100MHz. The output needs to be a single-ended voltage signal, with 10Vp-p.
For the same application with slower signals (a 16MHz DAC), I've used an architecture like this:
A simpler variant that should still work is to use resistors to ground in place of the transimpedance amps to convert the current to a voltage for the difference amplifier.
However, all the high speed amplifiers I can find, such as the THS3202 from TI, are current feedback amplifiers. As a result, their negative input has a low impedance, which - at least as far as I know - makes them unsuitable as differential input amplifiers.
How can I convert differential current outputs to a single ended voltage at these sort of frequencies, given the seeming unavailability of high speed voltage feedback opamps?