A Highly Linear 4 W Differential SOI-CMOS RF Switch

In this paper a highly-linear differential MOSFET-based stacked RF switch is demonstrated. The linearity improvement is achieved by stacking the switch branch well beyond the RF voltage handling requirements for minimizing odd-order nonlinear products and implementing a differential signal path on a switch die aimed at suppressing even-order nonlinear distortions. A hardware prototype of the switch arrangement operating at 850 MHz demonstrates <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{IP}_{3}$</tex> of 81.5 dBm and 89.6 dBm in ON and OFF states respectively, approaching the level of best-in-class ohmic RF-MEMS switches. The improvement is achieved at the expense of bandwith, which is limited to 200 MHz in the presented hardware demonstrator.