Abstract
In this paper, CMOS realizations of exponential function generators are considered and it is shown that the inherent square-law characteristic of the CMOS can be effectively used to produce the required exponential characteristic. While many of the existing exponential function generators rely on complicated coefficient settings procedure, in order approach, the circuit inherently realizes the required approximating function. However, the additional errors due to square-law model limitation can be alleviated by using so-called cascade realization technique. The functionality of the design is confirmed with 65 nm CMOS process technology with ± 0.5 V power supply in saturation region. In this design the power dissipation is 150 μ W. Simulation results proves the correctness of the theoretical analysis and proves the viability of the proposed structure.
| Original language | English |
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| Title of host publication | 2019 42nd International Conference on Telecommunications and Signal Processing, TSP 2019 |
| Editors | Norbert Herencsar |
| Publisher | Institute of Electrical and Electronics Engineers Inc. |
| Pages | 535-538 |
| Number of pages | 4 |
| ISBN (Electronic) | 9781728118642 |
| DOIs | |
| Publication status | Published - Jul 2019 |
| Event | 42nd International Conference on Telecommunications and Signal Processing, TSP 2019 - Budapest, Hungary Duration: 1 Jul 2019 → 3 Jul 2019 |
Publication series
| Name | 2019 42nd International Conference on Telecommunications and Signal Processing, TSP 2019 |
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Conference
| Conference | 42nd International Conference on Telecommunications and Signal Processing, TSP 2019 |
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| Country/Territory | Hungary |
| City | Budapest |
| Period | 1/07/19 → 3/07/19 |
Bibliographical note
Publisher Copyright:© 2019 IEEE.
Funding
This work is supported by Istanbul Technical University the Scientific Research Projects Unit Under Grant No. MDK-2019-41968. There are variety purposes and applications of EXPFG generators such as variable gain amplifier (VGA) [7], [8] and automatic gain control [9], [10]. As a result of this interest, there is a notable amount of literature on CMOS EXPFGs. However, these approaches can be classified into two main groups: circuits with weak inversion and with strong inversion devices. In the former, the exponential-like characteristic of the MOSFET inherently favors the design of the EXPFGs but the circuits suffer from the well-known limitations of weak inversion operation, while in the latter, additional circuits should be used to design EXPFGs as a result of the incompatible square-law characteristic of the MOSFET [11]. Among these papers, This work is supported by Istanbul Technical University the Scientific Research Projects Unit Under Grant No. MDK-2019-41968.
| Funders | Funder number |
|---|---|
| Istanbul Technical University the Scientific Research Projects Unit | |
| Firat University Scientific Research Projects Management Unit | MDK-2019-41968 |
Keywords
- Approximation
- CMOS current mode design
- Error
- Exponential function generator
- Translinear loop