Current-mode continuous-time filters using complementary current mirror pairs

A design of current-mode continuous-time filters for low voltage and high frequency applications using complementary bipolar current mirror pairs is presented. The proposed current-mode filters consist of simple bipolar current mirrors and capacitors and are quite suitable for monolithic integration. Since the filters are based on the integrator type of realization, the proposed method can be used for a wide range of applications. The frequency of the filters can easily be changed by the DC controlling current. A fifth-order Butterworth and a third-order leapfrog filter with tunable cutoff frequencies from 20 MHz to 100 MHz are designed as examples and simulated by SPICE using standard bipolar parameters.     

Single-element controlled oscillators using single FTFN

A novel configuration for realising sinusoidal oscillators using a single four-terminal floating nullor (FTFN) is proposed. Experimental results of six oscillators verified the theoretical analyses. All the capacitors are grounded or virtually grounded. Four of the proposed oscillators enjoy independent oscillation control through a single passive element and independent frequency control through another single passive element     

New voltage controlled oscillators using CFOAs

In this paper, some new current feedback operational amplifier (CFOA)-based voltage-controlled oscillators (VCOs) have been introduced. The proposed circuits offer a number of advantageous features over previously known CFOA-based VCOs. The workability of the presented circuits has been demonstrated using AD844 CFOAs and BFW10 FETs.     

Wien bridge oscillators using current conveyors

Realization of oscillators with single resistor control based on the circuit techniques of the second generation current conveyors (CC II) utilizing the separability of the Wien RC one-ports that are generalized through appropriate insertion of two more resistors is considered. The relative frequency stability is shown to improve over the conventional op-amp Wien bridge versions.     

Body controlled threshold voltage shifting variable gain current mirror

A programmable high-speed source-series-terminated driver with signal boost capability is presented. The driver uses only one main input data tap and is divided into main units and auxiliary units. A passive high pass filter is utilized to detect data transitions and control the inputs of the auxiliary units to enable a programmable amplitude boost for the output signal. The corner frequency of the high pass filter is adjusted depending on the data rate. Further, the amount of the high frequency signal boost can be adjusted depending on the loss of the channel. HSPICE simulations are used to demonstrate the performance of the driver at 10, 20 and 40 Gbps data rates. At 40 Gbps, the driver is capable of equalizing a PRBS9 data pattern signal through a channel that has a loss of 9 dB. At worst case conditions and 40 Gbps date rate, the driver achieves a differential eye-opening amplitude of 201 mVppd and an eye-opening of 0.952 UI. The driver is designed using 28 nm CMOS process and uses a nominal 1 V supply voltage. It consumes a maximum of 12 mW of at-speed power.     

Novel MOS-C oscillators using the current feedback op-amp

Three new MOS-C oscillators using the current feedback op-amp are presented. The proposed oscillators have the advantage of independent control of the oscillation frequency and the condition of oscillation. Two of the proposed MOS-C oscillators provide two outputs in phase quadrature. The third proposed oscillator provides two outputs in the balanced form. PSpice simulation results for the proposed oscillators are given.     

Multiphase sinusoidal oscillators using second generation current conveyors

A voltage-mode Multiphase Sinusoidal Oscillator realized using Second Generation Current Conveyors and only grounded passive elements is introduced in this paper. The proposed topology is suitable for realizing oscillators with both odd and even number of phases without modifying the core of the topology. Only non-inverting Current Conveyors are required for the construction of the oscillator's topology and this is a benefit from the discrete component implementation point of view. The behavior of the proposed topology has been evaluated, through experimental results, in the cases of three and six-phase oscillators.     

Research Note Two novel voltage( current) controlled integrable oscillators

Two novel voltage( current) controlled oscillator circuits are presented. Each circuit uses a single operational amplifier, a single operational transconductance amplifier, and either a single resistor or a single capacitor. In both circuits the frequency of oscillation can be adjusted by changing the biasing voltage( current) of the operational transconductance amplifier. Experimental results are included     

Power voltage current convertor using quasi complementary MOSFET current mirrors

A voltage current convertor is described having a quasi complementary class AB architecture that is particularly suited to implementation using discrete power MOSFETs. High-voltage mirror designs are presented, enabling the construction of sources with kilovolt compliance range, tens of watts of output power and greater than 100 kHz bandwidth. GΩ output impedance and distortion below 1% can be obtained with no trimming or transistor matching.     

Low-power low-voltage reference using peaking current mirror circuit

A low-power low-voltage bandgap reference using the peaking current mirror circuit with MOSFETs operated in the subthreshold region is presented. A demonstrative chip was fabricated in 0.35 /spl mu/m CMOS technology, achieving the minimum supply voltage 1.4 V, the reference voltage around 580 mV, the temperature coefficient 62 ppm//spl deg/C, the supplied current 2.3 /spl mu/A, and the power supply noise rejection ratio of -84 dB at 1 kHz.     

Current mode single resistance controlled oscillators using onlygrounded passive components

Two new current mode single resistance controlled oscillator (CM-SRCO) circuits are presented. Furthermore, it is demonstrated that the recently introduced fully differential current conveyor (FDCCII) is a versatile active element for realising CM-SRCOs. Simulation results with a 0.5 μm CMOS realisation of the FDCCII are included, validating the theoretical analysis     

Thermally reused solar energy harvesting using current mirror cells

This paper implements a simultaneous solar and thermal energy harvesting system, as a hybrid energy harvesting (HEH) system, to convert ambient light into electrical energy through photovoltaic (PV) cells and heat absorbed in the body of PV cells. Indeed, a solar panel equipped with serially connected thermoelectric generators not only converts the incoming light into electricity but also takes advantage of heat emanating from the light. In a conventional HEH system, the diode block is used to provide the path for the input source with the highest value. In this scheme, at each time, only one source can be handled to generate its output, while other sources are blocked. To handle this challenge of combining resources in HEH systems, this paper proposes a method for collecting all incoming energies and conveying its summation to the load via the current mirror cells in an approach similar to the maximum power point tracking. This technique is implemented using off-the-shelf components. The measurement results show that the proposed method is a realistic approach for supplying electrical energy to wireless sensor nodes and low-power electronics.     

Voltage transfer function synthesis using current conveyors

A synthesis procedure for generating current conveyor active filters is presented, and a novel network which realises the general 2nd-order voltage transfer function is given.<>     

A second current controlled current conveyor realization using Wilson current mirrors

The paper proposes a Wilson current mirror with double outputs and a bipolar second current controlled current conveyor (CCCII) circuit based on Wilson mirrors. The performance principle of the circuits is analysed and experiment results are given. The CCCII circuit has the following merits: high trace accuracy of voltage and current; high current output impedance; and good current stability.     

5.2 GHz SiGe HBT upconverter using active-inductor LC current mirror

A compact 5.2 GHz upconversion micromixer using the 0.35 /spl mu/m SiGe HBT technology is demonstrated. A bandpass and area-saving LC current mirror using the active inductor is incorporated to increase the conversion gain. The demonstrated upconverter has conversion gain of -3.5 dB, OP/sub 1dB/ of -10 dBm, and OIP/sub 3/ of 0 dBm.     

Generation of current conveyor based oscillators using nodal admittance matrix expansion

The residual stress in a polysilicon beam varies throughout its thickness and will cause a freestanding cantilever to curl upwards or downwards. Measurement of stress gradient for cantilever beam MEMS switches was studied by new procedure and its influences on pull-in phenomena of cantilever beam type were studied. The effect of non ideal anchors of fixed–fixed end type MEM switches were investigated in. The Generalized Differential Quadrature Method was used as a high order approximation to discretize the governing nonlinear differential equation yielding more accurate results with a considerably smaller number of grid points. Further, the results obtained were compared with other existing empirical and theoretical models.     

Surface-acoustic-wave delay-line controlled low-frequency oscillators

Surface-acoustic-wave delay line is used as the frequency controling element of a low-frequency oscillator, operating at a fundamental frequency of a few kilohertz. Some salient properties of such oscillators are discussed. Initial experimental results indicate that high-frequency stability can be obtained.     

On the realization of the current controlled current-mode amplifier using the current controlled conveyor

The current controlled current-mode amplifier proposed by Fabre et al. (1996, IEEE Transactions on Circuits and Systems—I, 43, 82) is reanalysed to show that it can work not only under small signal conditions, as suggested by Fabre et al., but also under large signal conditions. Simulation results which confirm the theory presented are included.     

Low-voltage CMOS adjustable current mirror

A novel scheme for an adjustable low-voltage CMOS current mirror is introduced. The proposed current mirror provides continuous gain adjustment, while it simultaneously features the attractive characteristic of low-voltage operation. The behaviour of the proposed topology has been experimentally verified through a first-order lowpass filter fabricated in AMS 0.35 μm CMOS technology.