Both the input signal and the gain setting resistor are AC-coupled using 0.1 µ F blocking capacitors (actually giving bandpass response with the low-frequency pole set to 32kHz for the component values shown). As discussed for Figure 1, this allows the midpoint bias formed by the two 1.87k Ω resistors to appear at both the input and output pins. The midband signal gain is set to +4 (12dB) in this case. The capacitor to ground on the noninverting input is intentionally set larger to dominate input parasitic terms. At a gain of +4, the OPA830 on a single supply will show 30MHz small- and large-signal bandwidth. The resistor values have been slightly adjusted to account for this limited bandwidth in the amplifierstage. Tests of this circuit show a precise 1MHz, −3dB point with a maximally-flat
resolution. Narrow-band technology such as Bluetooth confront with the problem of multipath fading which is described as signal loss due to the destructive interference of continuous wave (CW) signals . Next, the problem in NB is that the signals transmit are insecure because NB signals are easily detected and jammed . Narrow-band signals also facing a problem of poor range resolution for tracking applications and limited data rate because narrow RF bandwidth means narrow data bandwidth . In general, the RF performance of the Power Amplifier is excellent if it able to achieve the high gain, high output power, and high power added efficiency. By designing only a singlestageamplifier, we cannot provide a high gain, high output power, high power added efficiency, and high stability amplifier as expected. As for the different biasing circuit, active biasing does not offer much advantage over the passive biasing circuit so the matching networks can be changed to either lumped elements, shunt stub or quarter wave matching techniques for space reduction and cost saving. The developing of amplifier based on Distributed Amplifier technique will enhance performance in term of output power but affect the power added efficiency. There is also a problem of some conventional power amplifier design not support the whole range of UWB licensed bandwidth from 3.1 GHz to 10.6 GHz.
(iii) Final stage is to choose the optimization algorithm. In fact, authors have experienced many algorithms with gradients/heuristics approaches [9–11] in the circuit synthesis process; in this work, “Particle Swarm Optimization” (PSO) algorithm is employed as a simple and efficient by the derivative-free optimization tool in the syntheses process of the matching networks. In fact, nowadays evolutionary optimization algorithms have applied a wide range of electromagnetic problems, such as genetic optimization of the wide- band multimodal square horns for discrete lenses  and diffusion coefficient of the turbulent jet  PSO design of the electromagnetic absorbers , PSO synthesis of the phased arrays , cylindrical conformal arrays  and smart antennas , null placement and side lobe reduction of the radiation patterns for the linear arrays using the ant colony optimization . On the other hand some
Abstract—This paper presents a novel actuator-internal two degree-of-freedom (2-DOF) micro/nano positioning stage actuated by piezoelectric (PZT) actuators, which can be used as a fine actuation part in dual-stage system. To compensate the positioning error of coarse stage and achieve a large motion stroke, a symmetrical structure with an arch-shape bridge type amplifier based on single notch circular flexure hinges is proposed and utilized in the positioning stage. Due to the compound bridge arm configuration and compact flexure hinge structure, the amplification mechanism can realize high lateral stiffness and compact structure simultaneously, which is of great importance to protect PZT actuators. The amplification mechanism is integrated into the decoupling mechanism to improve compactness, and to produce decoupled motion in X- and Y- axes. An analytical model is established to explore the static and dynamic characteristics, and the geometric parameters are optimized. The performance of the positioning stage is evaluated through finite element analysis (FEA) and experimental test. The results indicate that the stage can implement 2-DOF decoupled motion with a travel range of 55.4×53.2 μm 2 , and the motion resolution
is dividing between the high series input resistance and low internal input impedance of the amplifier only a fraction of input will be amplified initially by the first stage which is built around Q1. Finally the output from the first stage is amplified by the second stage Q2. The emitter follower is inserted in this circuit for impedance matching between the two stages as shown in Fig.2.
As shown in Figure.7, when the power amplifier works at 2140MHz, drain voltage is 28V and the current is 500mA, the gain is about 15dB, the largest output power is about 47dBm, and the PAE at the largest output power is about 41%. By contrast with the performance from software design, it is obviously that the performances from big signal measurement have a little degraded. The deterioration is inevitable. Because the computer design and simulation is under the ideal situation, computer cannot think about the complex actual circumstances. But the overall measurements are under the real condition, there are so many potential factors impact the performance of the power amplifier, such as the circuit machining precision, sample transistor condition. After all, the performance of power amplifier has some deterioration, but it is acceptable.
Low noise amplifier (LNA) is one of the basic building blocks of any communication system. The purpose of the LNA is to amplify the received signal to an acceptable levels while minimizing the noise inside it. The low noise amplifier is used in communication systems to amplify very weak signals captured by the antenna, it is often located very close to the antenna thereby making losses in the feed-line less critical. It is necessary for the LNA to boost the desired signal power while adding very little noise and distortion as possible so that the retrieval of signal is possible in the later stages in the system. Usually Junction Field Effect Transistor (JFETs) and High Electron Mobility Transistor (HEMT) are used in LNA circuits because it’s offer high amplification in the first stage, these transistors are energy efficient but reduce the relative amount of shot noise. The general topology of the LNA is consists of three stages: the input matching network, (IMN), the amplifier itself and the output matching network, (OMN). In addition to select the appropriate active component, the IMN and OMN are critical factors in achieving the specified overall amplifier performances. The main topics of the article will include the following steps, bias design, circuit stabilization, noise optimization, input/output matching impedance network and complete circuit characterization. A circuit solution is presented along with complete simulation performance that is required by 2.4 GHz frequency. A number of design tools and iterative operators such as the Smith Chart Utility, Tune Parameter Utility, Optimizer Utility and the Schematic Design are all incorporated in Agilent ADS electronic design automation software, were used to perform the design process .
RC coupled, transformer coupled, direct coupled, Low and high frequency considerations, cascade amplifier, darlington pair, their performance. Analysis and design considerations of multistage amplifiers, effect of source and load resistance. Differential amplifiers, their types, small signal analysis, differential stage, level shifter.
The output of this is given as the input of common source amplifier, Since the gain provided by the differential amplifier is not sufficient. The second stage of the block diagram which is Common Source Amplifier provides the additional amplification that’s necessary. Common Source Amplifier is a one of three basic singlestage field effect transistor (FET) amplifier topologies, typically used as voltage amplifier.
No enclosure is shown for this amplifier as I do not have a suitable aluminum box available. However, it will be machined such that the loop wires pass through grommet-protected holes at one end, and there will be a PL-259 male UHF connector on the other end
Abstract: MEMS resonator based oscillators, however, are now a technical reality which are extremely cost-effective, very small in size in comparison with quartz crystal based oscillators and can be fabricated in the conventional CMOS process, monolithically. In this work a new sustaining amplifier is designed for a 17.22 MHz MEMS resonator which has an unloaded quality factor of 1000. A total transimpedance open loop gain of 122 dB-Ω has been achieved over the bandwidth of interest to drive this resonator for a sustained oscillation. Total DC power consumption of this sustaining amplifier is 6.3mW from a 1.8v DC source in 0.18μm CMOS process.
Figure 2 shows an AC-coupled, noninverting gain amplifier for single +5V supply operation. This circuit was used for AC characterization of the OPA698, with a 50 Ω source (which it matches) and a 500 Ω load. The mid-point reference on the noninverting input is set by two 806 Ω resistors. This gives an input bias current-canceling resistance that matches the 402 Ω DC source resistance seen at the inverting input (see the DC accuracy and offset control section). The power- supply bypass for the supply consists of two capacitors: one electrolytic 2.2 µ F and one ceramic 0.1 µ F. The power-supply bypass capacitors are shown explicitly in Figures 1 and 2, but will be assumed in the other figures. The limiter voltages (V H and V L ) and the respective bias currents (I VH and I VL ) have the polarities shown. These limiter voltages are adequately bypassed with a 0.1 µ F ceramic capacitor to ground. Notice that the single-supply circuit can use three resistors to set V H and V L , where the dual-supply circuit usually uses four to reference the limit voltages to ground. While this circuit shows +5V operation, the same circuit may be used for single supplies up to +12V.
response parameters of the proposed design such as bandwidth, gain bandwidth product, input/output noises and noise figure (NF) are improved in proposed (IF) amplifier. Moreover, a dual-input and dual-output (DIDO) IF amplifier con- structed from two symmetrical single input and single output (SISO) (IF) amplifier is proposed too. The idea is to achieve improved bandwidth, and flat response, because these parameters are very important in high frequency applica- tions. Simulation results that obtained by P-SPICE program are 1.2 GHz Bandwidth (BW), 3.4 GHz (gain bandwidth product), 0.5 mW DC consumption power (P c ) and the low total output noise is 12 nV Hz with 1.2 V single supply
The designed circuit is to meet the required specifications is shown in fig.1. The topology of this circuit is that of a standard CMOS op-amp. The designed CMOS operational amplifier circuit consists of three subsections, namely differential gain stage, second gain stage and bias strings. The main aim of this topology was able to successfully meet all of the design specifications. . The circuit operation has explained below.
As technology is scaling down the transistor lengths to reduce power consumption , the variability issues increases. Also static power dissipation and subthreshold leakage current becomes dominant at lower technology .Sacaling of CMOS in deca nanometer results in degradation of gmb/gm ratio to from 0.38 to 0.12 between representative 0.25 lm and 65 nm technologies. A common-mode adapter with a folded cascaded op-amp is used to reduce the common-mode voltage , circuitry and save power.In this paper the performance of CMOS devices at different technology for analog and mixed signal processing has been investigated .Op-amp ideally have infinite differential gain, infinite bandwidth ,infinite CMRR ,infinite slew rate in practical op-amp approaches to these values .Two stage op-amp is designed for different technology nodes of CMOS. Electrical characteristics of two stage op-amp at different technology nodes of CMOS are compared to study the technology scaling effects on the conventional CMOS .The effect of temperature variation on two stage op-amp at 32nm CMOS technology has been observed as temperature is also considered to be important factor for affecting the performance of circuit .
Abstract— This paper presents a design of Two Stage CMOS operational amplifier, which operates at ±2.5V power supply using umc 2µm CMOS technology. The OP-AMP designed is a two-stage CMOS OP-AMP. The OP-AMP is designed to exhibit a unity gain frequency of 4.416MHz and exhibits a gain of 96dB with a 700 phase margin. Design and Simulation has been carried out in LT Spice tools.
dominates the overall Noise performance in a typical receiver system that is why a pre amplifier of lowest possible Noise figure is introduced after antenna for better noise performance in most of the modern age receivers. Generally it is not possible to get both minimum noise figure and maximum gain for a Low noise amplifier, so a tradeoff is made between these parameters according to the requirement of the design. This tradeoff is made possible by creating different constant gain circles and Noise figure circles to select a usable tradeoff between between gain and noise figure.
1 Oryong-Dong, Buk-Gu, Gwang-Ju 500-712, Republic of Korea Abstract—In this paper, we present a wideband on-chip K-band RF front-end including a transmitter and receiver for vehicular FMCW radar applications using 0.18 µm CMOS process. To achieve wideband performance, an RC feedback circuit is applied to the input stage of amplifiers, as well as wideband passive circuits such as Marchand type baluns and Wilkinson type power dividers to the mixer LO port and transmitter output, respectively. The designed chip shows a 3- dB bandwidth of 6 GHz and 4.8 GHz for the receiver and transmitter, respectively. The receiver represents a gain of 18 dB and an input- referred 1 dB compression point of −9 dBm at an RF frequency of 24.15 GHz and an IF frequency of 100 kHz. The transmitter shows a power gain of 8.9 dB and an output power of 6.8 dBm at a frequency of 24.15 GHz. The total chip has a size of 1500 µm × 1270 µm while consuming 71 mA with a supply voltage of 1.8 V. Further, the designed RF front-end chip has been verified by radar performance tests such as the Doppler shift and range information. The test result for range information shows good agreement with theoretical expectations.
the BJT and MOS transistors . Ahmed and Mohammad modeled all the feasible four-impedance settings that give a good second-order two-stage Colpitts oscillator using two- port network transmission parameters, and this they tested by the use of BJT and MOS transistors in an experimental case . However, Ahmed addressed the task of Ahmed and Mohammad above for BJT and MOS in favour of two-port network transmission parameters for general design equations not limited to matched devices . In another study, Ahmed proposed two instances of two-port analysis namely, an elementary and the advanced; he derived the transmission matrices for small-signal equivalent models of the BJT and MOS transistors. He suggested that his derived two-port network is especially good to employ in network analysis because the expression is only derived once and is independent of the complexity of any transistor. Again, it uses inter-network connectivity in which network could be divided into series, parallel or cascade interconnects .