The THS3491 datasheet says it has a slew rate of 6000 - 8000V/uS. However looking at Fig 27 I see the output impedance rises significantly with frequency. So using this part to drive a transmission line with a series matching resistor is it necessary to limit the output slew rate way below what is possible to get a good low output impedance and minimize reflections ? For example say a 5V step at 5000V/us is1nS so assume 1nS rise, 1nS on and 1nS fall and 1nS off that,s a frequency of 250MHz. But from fig 27 Z out is around 15 Ohms at this frequency, so assuming this is inductive Z out would be sqrt (15^2 + 50^2) = 52 Ohms. So could limiting the slew rate be used to effectively lower Zout or is there a more elegant way to get a better broadband impedance match without signal loss or degradation ? I need 50+/-0.5 Ohms.