Publication detail

Differentiator circuits with scalable and electronically adjustable time constant and their application in phase shift evaluation

ŠOTNER, R. POLÁK, L. PETRŽELA, J. SEMENOV, D. LANGHAMMER, L. JAIKLA, W.

Original Title

Differentiator circuits with scalable and electronically adjustable time constant and their application in phase shift evaluation

Type

journal article in Web of Science

Language

English

Original Abstract

Two novel scalable and electronically adjustable differentiator designs are presented in this paper. These designs are based on special variable gain amplifiers extending well-known concept of standard single operational amplifier-based differentiators. The key novelty lies in their scalability, which allows for an enhanced time constant value by adjusting the ratio of resistors. Simultaneously, the special form of gain control using a DC voltage offers wide electronic tunability. The solution performs high input and low output impedance, both independent of frequency. Experimental testing demonstrated time constant adjustments in two configurations: from 64 ns to 4.5 mu s (a ratio of maximal and minimal value 70) and from 8.7 mu s to 183 mu s (a ratio of 21). As an application example, the proposed differentiator is utilized in the design of a readout system for an absolute phase shift difference to pulse width ratio converter, suitable for monitoring a very slow phenomenon such biosignals.

Keywords

Differentiator; Electronic adjustment; Operational amplifier; Scaling; Phase shift measurement; Time constant; Variable gain amplifier

Authors

ŠOTNER, R.; POLÁK, L.; PETRŽELA, J.; SEMENOV, D.; LANGHAMMER, L.; JAIKLA, W.

Released

3. 5. 2025

Publisher

ELSEVIER

Location

AMSTERDAM

ISBN

2090-4495

Periodical

Ain Shams Engineering Journal

Year of study

16

Number

9

State

Arab Republic of Egypt

Pages from

1

Pages to

12

Pages count

12

URL

https://www.sciencedirect.com/science/article/pii/S2090447925002308

BibTex

@article{BUT198146,
  author="Roman {Šotner} and Ladislav {Polák} and Jiří {Petržela} and Dmitrii {Semenov} and Lukáš {Langhammer} and Winai {Jaikla}",
  title="Differentiator circuits with scalable and electronically adjustable time constant and their application in phase shift evaluation",
  journal="Ain Shams Engineering Journal",
  year="2025",
  volume="16",
  number="9",
  pages="1--12",
  doi="10.1016/j.asej.2025.103489",
  issn="2090-4495",
  url="https://www.sciencedirect.com/science/article/pii/S2090447925002308"
}