Active filter design using operational transconductance amplifiers: A tutorial

Novel CMOS current mode shapers for front-end electronics are proposed. In particular, six semi-Gaussian shaper implementations based on second generation current conveyors and operational transconductance amplifiers are designed using advanced filter design techniques. Although all shaper architectures are fully integrated, they satisfy a relatively large peaking time. The topologies are analytically compared in terms of noise performance, power consumption, total harmonic distortion (THD), and dynamic range (DR) in order to examine which is the most preferable in readout applications. Design technique selection criteria are proposed in relation to the shaper structures performance. Analysis is supported by simulations results using SPICE in a 0.6 μm process by Austria Mikro Systeme (AMS).

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Novel Reconnection-Less Reconfigurable Filter Design Based on Unknown Nodal Voltages Method and Its Fractional-Order Counterpart

Elektronika ir Elektrotechnika ◽

10.5755/j01.eie.25.3.23673 ◽

2019 ◽

Vol 25 (3) ◽

pp. 34-38

Author(s):

Lukas Langhammer ◽

Roman Sotner ◽

Jan Dvorak ◽

Jan Jerabek ◽

Peter A. Ushakov

Keyword(s):

Fractional Order ◽

Filter Design ◽

Variable Gain Amplifier ◽

Pass Band ◽

Direct Transfer ◽

Electronic Control ◽

Operational Transconductance Amplifiers ◽

Variable Gain ◽

Transconductance Amplifiers ◽

High Pass

A novel solution of reconnection-less electronically reconfigurable filter is introduced in the paper. The filter is designed based on unknown nodal voltages method (MUNV) using operational transconductance amplifiers (OTAs) and variable gain amplifier (VGA). The structure can provide all-pass, band-stop, high-pass 2nd order functions, high-pass function of the 1st order and direct transfer from the same topology without requirement of manual reconnection. The proposed structure also offers the electronic control of the pole frequency. Moreover, fractional-order design of the proposed filter is also provided. The behaviour is verified by simulations using Cadence IC6 (spectre) software.

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Programmable OTA-Based Multifunction Active Filter

Active and Passive Electronic Components ◽

10.1155/1994/10413 ◽

1994 ◽

Vol 17 (1) ◽

pp. 21-27

Author(s):

Abdulrahman Khalaf Al-Ali ◽

Muhammad Taher Abuelma'atti ◽

Rizwan Ali Tiwana

Keyword(s):

Transfer Function ◽

Transfer Functions ◽

Active Filter ◽

Vlsi Implementation ◽

Operational Transconductance Amplifiers ◽

Digital To Analog Converters ◽

Centre Frequency ◽

Single Structure ◽

Multifunction Filter ◽

Transconductance Amplifiers

A fully programmable multifunction filter is presented. The filter uses four operational transconductance amplifiers and two capacitors. Analog switches are used to control the filter transfer function through a microcontroller. The user is provided control over the cutoff (or centre) frequency of the filter by controlling the auxiliary bias currents of the operational transconductance amplifiers via digital-to-analog converters. The circuit can simultaneously provide three programmable transfer functions in a single structure and can realize all the standard second-order filters. The circuit is attractive for VLSI implementation.

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