SachchidaNand Shukla

• MSc, PhD
• Professor at Dr. Ram Manohar Lohia Avadh University

In this paper a CMOS low pass filter circuit is designed by OTA using current driving technique. The filter is designed and simulatedin Cadence virtuoso 180 nm gpdk at the supply voltage of 1.8 V. Current driving technique used in the design has improved the gain and decreased the chip area of proposed CMOS-Low Pass Filter. Simulation results show...

The world of biomedical electronics is changing rapidly with the addition of newer circuit components and newer fabrication technologies day by day. The portability of biomedical devices is challenging due to size and battery life concerns and smaller geometries the poor noise performance and lack of linearity in performance is other big challenge....

Background: Contemporary linear electronic circuit designs frequently include small-signal low-power amplifiers as a fundamental building block. These amplifiers are widely used as LNAs (Low Noise Amplifiers) in the pre-amplifier stages of both low-frequency and high-frequency featured electronic circuits. Objectives: To review the recent advances...

Noise figure (NF) and linearity at higher frequencies are challenging tasks in Low Noise Amplifiers (LNAs) design. The existing LNAs impose limits on these parameters resulting in enhanced NF. In this paper, two ultra-wide band (UWB) small signal Sziklai pair based LNAs are proposed with improved linearity and minimum NF for high frequency wireless...

This paper presents the design and analysis of a low supply voltage Second-order OTA-C filter that gives high gain on a large range of frequencies for biomedical applications. Since the performance of the filter strongly depends on the basic building block transconductance cell, a low-power, highly linear, differential transconductance cell working...

Two circuit models of Small Signal amplifier, constituted with BJT-MOSFET hybrid unit under Sziklai pair topology are designed and analyzed using ‘PSpice’ and ‘Cadence Virtuoso and Spectre simulation tool (at GPDK 180nm technology)’ respectively. First amplifier (Circuit-1) uses PSpice user-defined model of BJT and MOSFET whereas the second amplifi...

Popularity of smart home gadgets gives rise to the demand for enhanced (wireless) RF power amplifiers. The global market of RF power amplifiers registered a CAGR of 3.2% between 2017 and 2021 and is expected to exhibit a growth of 15% from 2021 to 2032. The rising need of such RF amplifiers opens the path to a wide research in this field to fulfill...

A new paired configuration of opposite polarity BJTs, the “complementary Sziklai pair” is introduced in the series of multi-BJT-based devices like Darlington and Sziklai pair, and its viability is tested in small-signal common emitter (CE) and common collector (CC) amplifier configurations. The Darlington and Sziklai both face the problem of poor f...

As a novel approach, two different single-input RTL inverter (NOT gate) circuits using Sziklai and Darlington pairs are developed and qualitatively analyzed in the present manuscript. Performance of the proposed inverters are also compared with the conventional RTL inverter circuit. Respective inverter circuits use default PSpice models of NPN and...

In this paper, novel circuit designs of small-signal amplifiers with JFETs in Sziklai pair topology under common source and source-follower modes are demonstrated for the first time. With low transconductance, proposed amplifiers produce highest current gain of 1735.90, moderate voltage gain of 3.99, widest bandwidth of 2.17 GHz, highest power gain...

N-channel identical MOSFETs based Small-Signal Darlington pair amplifiers under triple transistor topology are simulated at GPDK 180nm, 90nm, and 45nm process technologies in Cadence Virtuoso and Spectre simulation tool. At 180nm technology, amplifier amplifies 1μV-100mV range AC signal with voltage gain (11.656), current gain (105.971), bandwidth...

Small-Signal Darlington pair amplifiers with MOS-BJT-MOS hybrid unit under triple transistor topology are demonstrated using PSpice and GPDK 180nm technology in Cadence Virtuoso and Spectre tool. The first circuit under Cadence tool produces moderate voltage gain (5.156), high current gain (2165.6), wide bandwidth (15.8866 GHz), high power gain (40...

New triple transistor topology based two circuit models of PNP driven Sziklai pair small-signal amplifiers have been proposed and analyzed in this paper. First circuit uses matched BJTs while second circuit employs lateral type of unmatched BJTs available at Generic Process Design Kits (GPDK) 180nm technology in Cadence virtuoso Spectre simulation....

In this paper, design and analysis of OTA based universal active filter at 180nm technology is done. It employs two OTAs and two capacitors with three input terminals and one output terminal. With this filter, low pass, high pass, band pass and band reject filters can be realized by the proper combination of input signal. These filter circuits have...

Small signal-to-noise ratio (SNR) and multiple noise sources, coupled with very weak signal amplitudes of bio signals make brain-computer interface (BCI) application studies a challenging task. The front-end recorder amplifiers receive very-weak signal (few μV) from high impedance electrodes and for efficient processing of such weak and low frequen...

A new PSpice Model of BJT and JFET is proposed and its hybrid combination is used in Sziklai pair topology to design small signal amplifier. The proposed amplifier with maximum voltage gain 30.41, maximum current gain 43.05 and THD 2.44% is capable of amplifying low magnitude signals in a frequency range distributed from 3.035Hz to 93.808Hz. This f...

Significant modification is done in PNP Sziklai pair based small signal amplifier by modeling of paired device and deletion of a prominent biasing resistor from the circuit. This culminates into two discrete amplifier designs, proposed for the present studies. Both the proposed amplifiers simultaneously produce high voltage and current gain. Howeve...

Ventricular Tachycardia (VT) is one of the leading causes of sudden cardiac death in the world. Prediction of VT is usually diagnosed by using Electrocardiogram (ECG) and requires expeditious treatment which reduces the mortality rate. The cross recurrence plot (CRP) toolbox is used for computing the recurrence rate values for both (healthy and unh...

A new approach of automatic classification of atrial fibrillation (AF) arrhythmia is proposed in this paper. Our approach is based on discrete wavelet transform method followed by cross recurrence quantification analysis (CRQA) for extracting the features of experimental ECG signals. The features like laminarity, determinism, entropy, trapping time...

Cardiac arrhythmias is a very uncommon life threating arrhythmia which can even cause sudden death. Healthcare professionals are always looking to find out the ways in order to reduce the death rate. The new method of feature extraction and classification of arrhythmias has been developed by the authors of this paper in their previous works. In thi...

A new small-signal amplifying system with Sziklai pairs in triple transistor topology is proposed and qualitatively analyzed for the first time. Proposed amplifier design may be used at preamplifier stage of EEG, Radio/TV receivers and other audible frequency range communication systems. Combination of Q1-Q2 transistors in the proposed design const...

BJT-MOSFET hybrid combination is used in Sziklai pair topology to design a novel circuit model of small-signal amplifier. Proposed amplifier can be tuned in 47KHz–245KHz frequency range. This circuit can amplify audio range signals swinging in 0.01–2mV range at 1KHz with an additional biasing resistance R A . Proposed amplifier with high voltage ga...

An Electrocardiogram (ECG) is graphical representation of the electrical movement of human heart and used in diagnosis of various heart diseases. The primary function of ECG analysis is correct detection of QRS complex and other ECG characteristics [1]. In this review paper, researchers provide a comparative study between four popular algorithms: n...

New circuit model of small-signal amplifier with three identical JFETs in Triple Darlington topology is proposed and qualitatively analyzed for the first time. Unlike CS-JFET amplifiers, the voltage gain of the proposed circuit is found considerably higher than unity. This amplifier successfully scales signal excursions swinging in 1- 35mV range at...

A New circuit model of two-stage small-signal amplifier using Darlington and Sziklai pairs is proposed for the first time. Proposed circuit is obtained by cascading a small-signal Darlington pair amplifier with that of Sziklai pair based small-signal amplifier with minor modifications. Proposed amplifier essentially uses two additional biasing resi...

The dielectric anisotropy and dispersion of the real and imaginary part of the permittivity of commercially important nematic mixture E-24 and its polymer composite were investigated in the frequency range from 1 kHz to 10 MHz, and temperature range to . The percentage optical transmittance and density have also been measured for both the systems....

New circuit model of a two-stage small-signal Sziklai pair amplifier is proposed for the first time. The proposed amplifier circuit, which is obtained by cascading a small-signal Sziklai pair amplifier (Stage-1) with triple-transistor based compound Sziklai amplifier (Stage-2), is analyzed on the qualitative scale. Performance of the proposed ampli...

New circuit models of 'Complementary-Symmetry Class-AB and Class-B Push-Pull Amplifiers' are proposed. The proposed Class-AB amplifier circuit, configured by matched Darlington pairs, possesses 62.83% efficiency with low harmonic distortion (0.94%). However the proposed Class-B amplifier that is configured by using Triple Darlington configuration o...

A new circuit model of small-signal wide-band voltage amplifier using Sziklai pair is proposed for the first time. The proposed amplifier circuit uses two PNP and one NPN transistors and two additional biasing resistances in its configuration. The upper half of the triple transistor system with transistors Q1 and Q2 constitute a Sziklai pair while...

A small-signal modified Sziklai pair (complementary Darlington pair) amplifier is proposed with an additional biasing resistance in the circuit. The proposed amplifier produces significantly high voltage gain with narrow bandwidth. Poor response of conventional Darlington pair amplifiers at higher frequencies is found to be absent in the proposed a...

White phosphor converted LEDs (pcLEDs) are important device for solid state lighting applications. It is found that at a higher ambient temperature, as expected in tropical countries like India, life of LED shortens even with the prescribed rated current. So it is important to estimate the 'useful life' of such devices under specified ambient condi...