Nil Tarim

Wide Dynamic Range High Output Impedance Current-mode Multifunction Filters with Dual-output Current Conveyors

Summary This paper reports five new single-input multiple-output current-mode multifunction filter circuits which can simultaneously realise three basic filter functions all at high impedance outputs. The circuits employ only the same type of active elements, grounded passive components, andno element matching conditions are imposed. The filters permit orthogonal adjustment of the quality factor Q and angular resonant frequency ω 0 . The active/passive sensitivities are shown to be low.

Realization of high-Q bandpass filters using CCCIIs

A new configuration for the realization of very high-Q filters with electronically controllable filter parameters is presented. For this purpose, first, a modification for the translinear CMOS CCCII and then, a new high-performance first-order allpass filter section are proposed. The main parameters of the resulting high-Q bandpass filter, ie. the center frequency and pole-Q can be independently adjusted via DC bias currents. It is also shown that the filter sensitivities with respect to capacitors mid intrinsic resistances are low. SPICE simulation results verify the theoretical analyses.

Simple and accurate nonlinear current conveyor macromodel

This paper describes a simple and accurate current conveyor macromodel which is suitable for simulation of active filter applications. The results obtained show that the proposed macromodel approximately represents the current conveyor with the same accuracy of the semiconductor, SPICE device models, but with a considerably reduced computer time.

PID-Controlled PLL for Fast Frequency-Hopped Systems

In this work, a novel aided-acquisition technique based on proportional-integral-derivative (PID) control of a phase-locked loop (PLL) is presented. This is achieved by inserting a control block into the PLL during acquisition where originally the output frequency/phase is controlled by a PI controller. This significantly reduces the settling time of the PLL which is important for certain applications such as WLANs where fast frequency-hopped spread-spectrum methods are used. Simulations show that the proposed structure reduces the settling time by 75%.

A tunable active filter in CMOS for RF applications

An active radio frequency (RF) filter based on floating active inductor circuits is presented in this work. For demonstration purposes, a third-order Chebyshev lowpass filter with an LC ladder structure has been designed for GSM applications. The filter has a cutoff frequency of 900 MHz and 0.4 dB ripple, and is tunable between 890 MHz and 960 MHz, consumes 10.5 mW power, and occupies an area of 96 mumtimes135 mum when laid out using the UMC 0.13 mum CMOS process which provides an area reduction of 80% compared to its passive filter counterpart.

A new high output impedance current-mode universal filter with single input and three outputs using dual output CCIIs

This paper presents a new current-mode universal filter using dual output current conveyors. The proposed filter can simultaneously realize three basic filter functions all at high impedance outputs. The circuit employs only the same type active elements and grounded passive components. The resonant angular frequency and the quality factor can be orthogonally controllable. The passive sensitivities are shown to be low. PSPICE simulation results are also included.

The effects of CCII non-idealities on voltage-mode active filters

In active filters, the performance of the active element plays an important role in the overall performance of the filter, besides the filter configuration itself. In this paper, we will investigate the effects of current conveyor non-idealities on a certain class of filters which consists of four current conveyors and seven nodes, and derive analytical expressions for the filter parameter deviations in terms of non-ideality terms. The results obtained apply to all filters under this class which are considerable in number. This will enable us to determine the requirements for the current conveyor non-ideality terms in order to obtain a specified filter performance. A comparable demonstration of the filter transfer functions for two example current conveyor circuits will be given. Simulations including three types of filters, namely, the bandpass, lowpass and highpass filters, confirm the analytical expressions obtained.

A new voltage-mode universal filter based on a lossy inductor simulation

A new voltage-mode universal active filter employing only two CCII+s and a minimum number of capacitors is proposed. The active and passive sensitivities are lower than unity and not dependent on the quality factor Q. The use of only CCII+s simplifies the configuration. Dynamic range of the filter is studied and a simple formula is derived for input signal amplitude not causing clipping problems for the proposed bandpass filter. Simulated results verifying the theoretical approaches are also included.

An X-band SiGe low-noise amplifier with high gain and low noise figure

This paper presents the design of a low-noise amplifier (LNA) with high gain and low noise figure (NF), targeting the X-band, in 0.25 mum SiGe BiCMOS process provided by IHP. Simulation results show that at 10 GHz, the proposed LNA has a noise figure of 2.295 dB, with both input and output impedances matched to 50 Omega, an input return loss of -30.22 dB, an output return loss of -17.02 dB, and a voltage gain of 20.74 dB while dissipating 7.5 mW power from a 2.5 V power supply. The circuit occupies a chip area of 590 times 765 mum2.

Novel Voltage-Mode Structurely Allpass Filters Without External Passive Components

In this work, two voltage-mode filters, a first-order and a second-order structurely allpass filter, realized with active components only, are presented. The circuits employ only operational transconductance amplifiers (OTA) and internally compensated operational amplifiers (OA). The second-order filter parameters are independently adjustable. Simulation results are included to verify theory