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Highlights: [•] We model the transmission line with frequency dependent parameters in the harmonic domain. [•] Reformulate the relationship for voltages and currents between the receiving end and any point on the transmission line. [•] Propose a representation of the TCSC given by a complex admittance matrix, which includes the cross-couplings between harmonic frequencies. [•] Presents a harmonic propagation analysis, including the effects of all the harmonic content and the cross coupling between harmonics. [•] Presents the harmonic interaction between the linear and nonlinear parts in the system. [ABSTRACT FROM AUTHOR]

In this article a current-mode, second-order, CT Sigma-Delta modulator operating at a sampling frequency of 25 MHz and with an oversampling ratio of 64 has been designed. The modulator consists of current-mode, differential integrators based on a single-stage folded cascode topology and switched capacitors DACs cells generating exponential feedback waveforms. The modulator was analysed in detail from both a system- and a circuit-level point of view. A 'short' exponential DAC pulse, namely, an exponential pulse whose time constant is lower than the pulse width, was used to improve jitter rejection. Modulator feedback coefficients were analytically derived for an exponential feedback waveform. Jitter considerations paying special attention to its impact on CT Sigma-Delta modulators were presented, and two different contributions distinguished: independent jitter and accumulated jitter. Finally, functional- and transistor-level simulations have been accomplished to obtain significant features of the modulator performance. [ABSTRACT FROM AUTHOR]

A very low voltage solution for the realization of the hold capacitor in a Track&Hold circuit based on an open-loop architecture is introduced. The circuit is a modification based on the switched opamp approach of the Track&Hold circuit using Miller Capacitance. Simulations show that the circuit is able to operate at 1V 1MS/s with a Total Harmonic Distortion of -64 dB @ 100 kHz and a very low power consumption of 80 µW. [ABSTRACT FROM AUTHOR]