A new structure, 200-MHz, -60 dB distortion linedriver for 1000Base-T Ethernet

A new way to design a linedriver with high speed and high linearity is presented now. This type of linedriver has a structure similar to the fake-full differential architecture and applies deeply negative feedback principle to predigest the topology structure of a circuit and to achieve a better function. The simulation result shows that: the large-signal closed-loop bandwidth is in excess of 200-MHz. And it can drive a 100-MHz, 3-Vpp sinewave across an equivalent 50-Ohm load from a 3.3-V supply with linearity -60dB. When inputting a couple of differential pulse signals of 0.5-Vpp amplitude and 125-MHz frequency, the quiescent power consumption of the linedriver is 33 mW, and the output signal rising or falling time is 1.7 ns. The die area is 0.12 mm/sup 2/. And the chip has been sent to the Europractic .35 um foundry to be manufactured.