Abstract: Various circuit techniques employ a transconductance (gm) cell in control loops to implement circuits such as phase locked loops and delay locked loops that are capable of operating at ultra high frequencies with improved precision and noise performance. The gm cell is designed to operate on an analog input signal with a very small swing and more gradual transition edges. These characteristics allow implementation of high frequency circuits and systems including, for example, transceivers for fiber optic channels, disk driver electronics and the like.

Abstract: An integrated circuit transformer includes multiple metal layers in the structure of an integrated circuit in which are formed a first spiral inductor and a second spiral inductor. The first spiral inductor is aligned with and beneath the second spiral inductor such that the first spiral inductor acts to magnetically excite the second spiral inductor, while shielding it from resistance losses to the substrate.

Abstract: An integrated circuit voltage-controlled oscillator includes an amplifier, a low Q LC resonator coupled to the amplifier, and a voltage-controlled variable delay element connected to delay feedback between an output and an input of the amplifier.