In this paper we present the results of both experimental investigation and analytical modelling of γ-irradiation effects on basic electrical characteristics of power VDMOS transistors. First, an analytical model that yields the drain current and transconductance dependencies on gate oxide charge density is developed. The experimental data are utilized to establish an analytical relation betwee...

A realization of a current-controlled current-mode four-phase quadrature oscillator based on current differencing transconductance amplifiers (CDTAs) is proposed. The proposed oscillator circuit employs only three CDTAs and two grounded capacitors, which can provide four high output impedance sinusoidal current outputs with four-phase difference. The oscillation condition and oscillation freque...

This paper presents charge-based continuous equations for the transconductance and output conductance of submicrometer Graded-Channel (GC) Silicon-On-Insulator (SOI) nMOSFET. The effects of carrier velocity saturation, channel length modulation and drain-induced barrier lowering were taken into account in the proposed equations. Experimental results were used to test the validity of the equatio...

Recently analog circuit designers are interested in structured optimization techniques to automate the process of CMOS circuit design. Geometric programming, which makes use of monomial and posynomial expressions to model MOSFET parameters, represents one such approach. The extent of accuracy in finding a global optimal solution using this approach depends on the formulation of circuit and devi...

An intermediate frequency (IF) variable gain amplifier (VGA) with exponential gain control for a radio receiver is fabricated in 0.25-μm CMOS technology. The techniques to improve the bandwidth and to reduce temperature dependence of gain are described. The complete VGA is composed of two stages of linearized transconductance VGA and three stages of fixed gain amplifier (FGA). The complete VGA ...

Heterostructure field-effect transistor design criteria are proposed in this study. GaAs pseudomorphic high electron mobility transistors (pHEMTs) are extensively applied to radar satellite receipt dispatcher antenna, and cell phone. Devices for various doped type and different material heterostructure are simulated and analyzed. The δ-doped InGaP/InGaAs/GaAs pHEMT with high density of two dime...

A low-voltage high-linearity wideband current differencing transconductance amplifier (CDTA) is presented in this paper. The CDTA consists of a current differencing circuit and a cross-coupling transconductance circuit. The PSPICE simulations of the proposed CDTA show a good performance: -3dB frequency bandwidth is about 900 MHz, low power consumption is 2.48 mW, input current linear range is ±...

The potential impact of GaN-based high electron mobility transistor (HEMT) with two channel layers of GaN/InAlGaN is reported. Using two-dimensional and two-carrier device simulations, we investigate the device performance focusing on the electrical potential, electron concentration, breakdown voltage and transconductance (gm). Also, the results have been compared with structure of AlGaN/GaN HE...

This paper presents a novel quadrature sinusoidal oscillator using second-generation current conveyor transconductance amplifier as an active building block. The proposed circuit employs only a single second-generation current conveyor transconductance amplifier, four passive components. The proposed circuit offers the advantages of independent control of the condition of oscillation and freque...

This paper presentes a simple floating immittance simulation circuit employing only one differential voltage current conveyor transconductance amplifier (DVCCTA) and two grounded passive components. The proposed floating simulator circuit can realize floating inductor, capacitor or resistor depending on the passive element selection. The equivalent value of the realized simulator can be tuned e...