Patent ID: 8669804

Claim:
A unit cell for a sub-circuit of a digitally tunable capacitor (DTC), the sub-circuit being adapted to be coupled between a first RF terminal and a second RF terminal, the unit cell comprising: a plurality of 2N stacked switches, the stacked switches proceeding from a first switch closest to the first RF terminal and farthest from the second RF terminal to an 2N-th switch farthest from the first RF terminal and closest to the second RF terminal, wherein: N represents an integer greater than or equal to two; the first RF terminal is a terminal through which a voltage source is adapted to be coupled to the unit cell; the 2N stacked switches comprise a first set of N switches close to the first RF terminal and far from the second RF terminal and a second set of N switches far from the first RF terminal and close to the second RF terminal, each switch of the first set and second set being coupled in parallel with a compensating capacitor thus providing a compensated capacitance value for that switch when the switch is in an off state, and each switch of the first set has a corresponding switch of the second set having the same compensated capacitance value, wherein the first switch and the 2N-th switch are equal in size and are the largest switches among the plurality of 2N switches.