The design and performance of a rail-to-rail low-voltage CMOS fifth-order elliptic low-pass GM-C filter for baseband mobile communication are presented. The operational transconductance amplifier ...(OTA) used in this filter is a low-voltage rail-to-rail voltage-to-current converter (V-I converter). In this V-I converter, an N-type V-I converter cell is connected in parallel with its counterpart, a P-type V-I converter cell, to achieve common-mode (CM) rail-to-rail operation. Two maximum-current selecting circuits and an output current subtraction circuit are utilized to generate constant-g/sub m/ output currents for this OTA. This fifth-order elliptic low-pass GM-C filter operates at a supply voltage of 3 V and has a cutoff frequency of 280 to 405 kHz. It provides up to 700 mV/sub pp/ output with 1% total harmonic distortion (THD), dissipates 2.48 mW at V/sub cm/=1.5 V, and occupies 1.62 mm/sup 2/ in a 1.2-/spl mu/m CMOS technology.
Millimeter-wave signals are typically generated by frequency multiplication in modern single-chip or multichip module (MCM) systems. Consequently, the multiplication efficiency, spurious rejection, ...and size of the frequency multiplier ultimately limit the integration level and cost of these systems. This paper points to the size reduction of millimeter-wave frequency doublers by evaluating artificial transmission lines (ATL's) as a means to minimize the size of the low-impedance shunt stubs. As a result, we developed a 40-GHz frequency doubler, which used only 0.6-mm/sup 2/ area on a monolithic microwave integrated circuit. Despite the area minimization, the doubler exhibited state-of-the-art conversion loss of 1 dB over 10% bandwidth and rejected the fundamental frequency signal by more than 20 dB over 25% bandwidth. Reported herein is the novel simulation of the frequency doubler with active harmonic loads. Included in this paper are theoretical evaluation and simulation of ATL's with models for lumped components and verification of the results by electromagnetic simulation. Due to the high efficiency, low area requirement, and over 20-dB rejection of the fundamental signal, this miniaturized ATL frequency doubler can be used as a building block in the generation of local-oscillator signals in single-chip and MCM millimeter-wave systems.
L’harmonisation du SMQ dans un LBM multi-sites est indispensable pour répondre aux exigences de la norme ISO 15189. Elle passe par une communication interne efficace et maîtrisée, difficile à mettre ...en place dans un laboratoire étendu à 15 sites techniques, éclatés sur 2 régions administratives, et regroupant plus de 200 personnes.
Pour pallier à ces difficultés, nous avons complété un réseau déjà établi de correspondants qualité, matériel et informatique dans chaque site par un groupe de 6 correspondants qualité multi-sites (CQM) compétents et volontaires, chacun chargé d’un sous-territoire régional.
Leur mission est de correspondre directement avec le personnel des sites dont ils ont la charge (techniciens, correspondants qualité et biologistes), de remonter les difficultés et interrogations rencontrées sur le terrain et de restituer au personnel les réponses et décisions prises lors de réunions avec le responsable qualité et le biologiste responsable du LBM. En 3ans, de nombreuses réunions, dont les comptes rendus sont diffusés à tout le personnel, ont ainsi permis de répondre précisément et uniformément à une multitude de questions très pratiques sur des sujets très divers.
Ce maillage territorial par les CQM a renforcé efficacement la communication interne, a facilité le déploiement harmonieux du SMQ au sein des sites, et s’est avéré très efficace en termes d’adhésion du personnel au respect des pratiques établies et d’implication dans la démarche qualité du laboratoire.
Cette harmonisation a été reconnue et considéré comme un point fort de la démarche par les évaluateurs du Cofrac et a largement contribué à l’accréditation du LBM multi-sites en 2014.
Subharmonic sampling is a discrete-time solution to the signal downconversion problem. It can be used either to replace a traditional continuous-time mixer in a superheterodyne receiver or can be ...combined with other discrete-time analog signal processing blocks in novel receiver architectures. We present a 2-GHz bandwidth integrated mixer based on subharmonic sampling operating at sampling frequencies from 40 MHz to 1.5 GHz. The conversion efficiency is optimized by appropriate choice of the clock duty cycle. The sampler uses a two-diode topology with a 3-V supply. The downconversion loss for the passive sampler is 1 dB and the total system gain 3 dB, The mixer achieves IIP3 of +16-dBm and -1-dB compression +7 dBm for a single-tone input. The circuit was implemented with a 0.6-/spl mu/m GaAs metal-semiconductor field effect transistor (MESFET) process.
A system is presented for the accurate measurement of high-frequency periodic time-domain voltage and current waveforms of a nonlinear microwave device. The measurements are performed in the time ...domain using a high-speed sampling oscilloscope. The results are Fourier-transformed into the frequency domain for error correction and then back into the time domain. An error-correction algorithm is presented that makes it possible to obtain accurate waveforms in spite of nonideal system components. Practical difficulties in measurement-system characterization are also discussed. An accurate circuit model for the measurement fixture is developed and its element values are determined. Measurement results are given showing the waveforms in a microwave transistor operated in the nonlinear region. The errors caused by signal processing are discussed.< >
One of the main objectives in CNN design is to have as small a cell size as possible and because there are normally 19 synapses implemented in each cell, we cannot select an architecture that is very ...area consuming. In our approach we simplify the multiplication procedure without losing the overall input-output mapping. In that way the synapses can be built from very few transistors and the cell layout can be made small. What has been noticed is that when the initial values of the network are bipolar and when the obtained network output is also bipolar, in almost every case we can use a high-gain output nonlinearity to replace the unity gain. Another required modification is to move the whole processing into a positive range.
An integrated active microwave filter employing high-Q active inductance simulating circuits is presented in this paper. Heterojunction bipolar transistor (HBT) technology is best-suited for this ...specific application facilitating the design and giving optimum performance with low power consumption. The prototype triple-resonator filter operates at 2.32 GHz with a 300 MHz -3-dB bandwidth. The power consumption is only 25 mW drawn from a 3-V supply.
A low-voltage rail-to-rail CMOS V-I converter Chung-Chih Hung; Ismail, M.; Halonen, K. ...
IEEE transactions on circuits and systems. 2, Analog and digital signal processing,
06/1999, Letnik:
46, Številka:
6
Journal Article
This paper presents CMOS low-voltage rail to-rail voltage-to-current (V-I) converters which could be used as basic building blocks to construct low-voltage current-mode analog very large scale ...integration (VLSI) circuits. In the circuit, an n-type V-I converter cell is connected in parallel with its p-type counterpart to achieve common-mode rail to-rail operation. A linear differential relationship of the n-type V-I converter, or its p-type complement, is obtained using a new class-AB linearization technique. The constant transconductance value is obtained by manipulating the DC bias currents of n- and p-type V-I converter cells. The circuit can operate from rail to rail with a power supply of 3 V or less, depending on the VLSI technology and the DC bias current level.
Most radio frequency voltage-controlled harmonic oscillators are tuned by changing the capacitance of a pn-junction diode. The inadequate capacitance tuning range of the pn-junction diode severely ...limits the achievable frequency tuning range of the oscillator. Two methods for extending the tuning range of monolithic LC-oscillators are discussed in this paper. The first approach is to use actively synthesized capacitor based on the Miller effect instead of a pn-junction varactor diode for the VCO tuning. An analytical model is developed for studying the capacitance tuning range and the corresponding Q-value. In the second approach we are using a balanced variable impedance converter for the VCO tuning. In this approach tuning is based on current steering using the Gilbert cell. Altogether nine experimental circuits have been fabricated with a 0.8 mu m BiCMOS process. All circuits oscillate around 2 GHz and tuning ranges exceeding 30% have been measured.
A set of integrated circuits for 60 GHz radio front-end Karkkainen, M.; Varonen, M.; Riska, J. ...
2002 IEEE MTT-S International Microwave Symposium Digest (Cat. No.02CH37278),
2002, Letnik:
2
Conference Proceeding, Journal Article
This paper describes results obtained within the MMIC research activity at the Helsinki University of Technology (HUT). These MMICs were developed for a 60 GHz broadband radio front-end. A set of ...circuits is reported including power, low noise amplifiers, mixers and signal generation circuits. They have been fabricated with a commercially available 0.15 /spl mu/m GaAs pseudomorphic HEMT technology. Finally, the performance of the circuits was measured at 60 GHz frequency: The power amplifier has 14 dBm output compression point and 15.5 dB small signal gain. The low noise amplifier exhibits 24 dB of gain with 3.5 dB noise figure and the up-conversion mixer circuit has 12.7 dB of conversion loss.
