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Multistage amplifiers have become appropriate choices for high‐speed electronics and data conversion. Because of the large number of high‐impedance nodes, frequency compensation has become the biggest challenge in the design of multistage amplifiers. The new compensation technique in this study uses two differential stages to organize feedforward and feedback paths. Five Miller loops and a 500‐pF load capacitor are driven by just two tiny compensating capacitors, each with a capacitance of less than 10 pF. The symbolic transfer function is calculated to estimate the circuit dynamics and HSPICE and TSMC 0.18 μm. CMOS technology is used to simulate the proposed five‐stage amplifier. A straightforward iterative approach is also used to optimize the circuit parameters given a known cost function. According to simulation and mathematical results, the proposed structure has a DC gain of 190 dB, a gain bandwidth product of 15 MHz, a phase margin of 89°, and a power dissipation of 590 μW.

ABSTRACTIn this study, a monolithic microwave integrated circuit channelized active bandpass filter using noise cancelling circuit is presented. We propose a new structure on the channelized bandpass filter. By adding output currents of three bandpass filters and using current to voltage converter, the proposed three-channel bandpass filter is achieved. In designing each bandpass filter, a recursive differential structure has been used. Also, to decrease the noise of this filter, a new noise cancelling circuit operated in a wide range from 1 to 7 GHz is investigated. By using this circuit, input impedance matching is obtained simultaneously. The chip has been implemented using GaAs 0.15 µm technology and occupies an area of 2.5 × 2.4 mm2. The post layout simulation results show a noise figure of 1.4–3.7 dB with a good input and output impedance matching less than −10 dB. The centre frequencies of channelized filter are 2, 4, and 6 GHz while the voltage gains are 18, 12, and 10 dB, respectively. The circuit power consumption is 250 mW.

ABSTRACTAn analytic design guide to design a three-stage cascade CMOS operational amplifier compensated by AC boosting frequency compensation (ACBC) method is presented in this paper. The procedure allows electrical parameters such as gain bandwidth (GBW) product or phase margin to be related to the value of circuit elements such as aspect ratio or biasing currents of transistors. The presented design guide is suited for pencil-and-paper design and yields accurate performance without unnecessary circuit constraint introduction. Simulation results using TSMC 0.18 µm CMOS process verifies accuracy and robustness of proposed procedure. Various load capacitors and circuit conditions are simulated and, based on obtained results, the presented design guide is comprehensive and efficient since it leads us from frequency response parameters to aspect ratio of MOSFETs.

ABSTRACTIn this paper, we report and design a new kind of AlGaN/GaN/InGaN/GaN high electron mobility transistor (HEMT), consisting of T-shaped gate with low resistance contacts, and the performance of a cascode topology low noise amplifier (LNA) with shunt-feedback technique for wideband and flat gain, based on mentioned HEMT. The proposed LNA has ∼17.5 dB of gain from 3 to 10 GHz with a noise figure of 0.7–1.1 dB in the band of interest. The direct current (DC) and radio frequency advantages of the reported HEMT and the superior flat gain performance of the cascode LNA are demonstrated.

Abstract: We propose a feedback type oscillator and two negative resistance oscillators. These microwave oscillators have been designed in the S band frequency. A relatively symmetric resonator is used in the feedback type oscillator. The first negative resistance oscillator uses a simple lumped element resonator which is substituted by a microstrip resonator in the second oscillator to improve results. The negative resistance oscillator produces 4.207 dBm and 7.124 dBm output power with the lumped element resonator and microstrip resonator respectively, and the feedback type oscillator produces −10.707 dBm output power. The feedback type oscillator operates at 3 GHz with phase noise levels at −83.30 dBc/Hz and −103.3 dBc/Hz at 100 kHz and 1 MHz offset frequencies respectively. The phase noise levels of the negative resistance oscillator with the lumped element resonator are −94.64 dBc/Hz and −116 dBc/Hz at 100 kHz and 1 MHz offset frequencies respectively, at an oscillation frequency of 3.053 GHz. With the microstrip resonator the phase noise levels are −99.49 dBc/Hz and −119.641 dBc/Hz at 100 kHz and 1 MHz offset frequencies respectively, at an oscillation frequency of 3.072 GHz. The results showed that both the output power and the phase noise of the negative resistance oscillators were better than those of the feedback type oscillator.

The S band limits from 2 to 4 GHz, is part of the electromagnetic spectrum’s microwave band. It is used by radars, satellites and some communications. This paper is concerned with the theory and design of 3 GHz feedback type and negative resistance oscillators by using Aiglent ADS software simulator with GaAs ED02AH 0.2-μm technology, and comparison of their results. A lumped element resonator has used in the design of feedback type oscillator and a negative resistance oscillator has utilized a microstrip resonator. The negative resistance oscillator operates at 3.072 GHz with phase noise levels at -99.49 dBc/Hz and -119.6 dBc/Hz at 100KHz and 1 MHz offset frequencies respectively. The phase noise levels of feedback type oscillator are -83.30 dBc/Hz and -103.3 dBc/Hz at 100KHz and 1 MHz offset at oscillation frequency of 3 GHz. Furthermore, we compared the output power of these oscillators and negative resistance oscillator showed 7.124 dBm, and feedback type oscillator presented -10.707dBm.

This paper describes the 0.35 um SiGe BiCMOS Voltage Controlled Oscillators (VCOs). One is Cross-coupled VCO, and the other one is Colpitts VCO. Both of them are designed with the same method. For achieving lower noise, the differential structure was used at this design. The center frequency for Cross-coupled VCO and Colpitts VCO is 5GHz. The tuning range of Cross-coupled VCO and Colpitts VCO is 1750 MHz and 230 MHz, respectively. The phase noise and the figure of merit (the FOM) for Cross-coupled VCO, are -155.5 dBc/Hz and -224.7dBc/Hz @1MHz offset frequency at an oscillation frequency of 5GHz, respectively. The phase noise and the figure of merit value of Colpitts VCO is -134.1 dBc/Hz and -200.3 dBc/Hz at the 1MHz offset from the center frequency of 5GHz. For The DC current of Cross-coupled and Colpitts VCO is 2 mA and 4 mA , respectively. Considering a 3.0 V supply Cross-coupled voltage (VCC) for both VCOs. The output power of Cross-coupled VCO is -3.94 dBm and the Colpitts VCO achieves an output power of 5.428 dBm. Agilent ADS software is used throughout this work