A highly linear programmable-gain amplifier (PGA) is fabricated using a 0.35m CMOS technology. High linearity and constant wide bandwidth are achieved by using a high-gain amplifier with low input impedance and resistor-network feedback. The voltage gain is varied by digitally controlling the input switched resistors. The distortion of a switched resistor has been analyzed using the Volterra se...

In this paper, a voltage mode variable gain amplifier (VGA) is presented. A fully differential implementation is used to suppress the common mode noise and increase the dynamic range. The gain of the proposed VGA can be digitally controlled from 0 to 53 dB, with a 1 dB resolution. The gain control is performed in two stages; coarse control with a 6 dB resolution and fine control with a 1 dB res...

In this paper, an Automatic Gain Control (AGC) loop which is based on a linear-in-dB Variable Gain Amplifier (VGA) is proposed. The VGA structure is based on simple nMOS differential pairs with variable tail currents. The linear-in-dB gain tuning schema is designed using a novel exponential current generator which also offers temperature compensation of the VGA’s gain. The gain of the VGA is tu...

This paper proposes a high gain and wide bandwidth amplifiers with numerical approach. It is improved that the low-frequency characteristics and the range of gain refers to direct-coupling. The gain is controlled with numerical approach,which makes the gain stability. It is easy to control the gain of the multistage amplifier with adopting uniform gain control voltage. It is useful for numerica...

The mass usage of traditional fossil energy has adversely affected the environment on a global scale, such as environmental pollution and greenhouse effect. Meanwhile, there has been a growing demand for energy with the development of society. Since traditional fossil energy is not renewable, it is faced with the problem of energy shortage. Solar energy and hydrogen energy are promising, and ph...

This paper describes a CMOS voltage reference circuit which occupies small die area and has less than 1.25 V of output voltage. The reference voltage is determined by a resistor ratio, and it is possible to set the reference voltage from zero to near the supply voltage with the same temperature independence as those of Widlar’s and Brokaw’s bandgap voltage references. The temperature-independen...

Solar Photovoltaic (PV) has emerged as a major contender to serve as an alternative energy source and is currently playing a leading role in supporting the existing conventional power generation systems. Several solar PV systems require a high gain front end dc-dc converter. Conventional dc-dc converters can offer limited gain and their efficiency drops as the gain requirement increases. This p...

constitutively phosphorylated RyR2 at Ser2814 showed a higher incidence of Ca sparks and increased susceptibility to pacing-induced AF compared with controls. The relationship between [Ca ]i and INCX density revealed INCX upregulation in cAF. Spontaneous Ca release events accompanied by inward INCX currents and delayed afterdepolarizations/triggered activity occurred more often and the sensitiv...