Radio Frequency Integrated Circuit Design - Webs

The Use and Design of Passive Circuit Elements in IC Technologies
Figure 5.20 Equivalent circuits for the case where (a) the side with the underpass is grounded;
(b) the underpass is not grounded; and (c) the circuit is driven differentially.
differentially is clearly better. In addition, in this case, the Q keeps rising to a
higher frequency and higher overall value.
5.17 Layout of Spiral Inductors
The goal of any inductor layout is to design a spiral inductor of specified
inductance, with Q optimized for best performance at the frequency of interest.
In order to achieve this, careful layout of the structure is required. The resistance
of the metal lines causes the inductor to have a high series resistance, limiting
its performance at low frequencies, while the proximity of the substrate causes
substrate loss, raising the effective resistance at higher frequencies. Large coupling
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