[paper] OTA using the Open Sky130 PDK

Carolina Vieira Souza, Edmar Philipe Ribeiro

and Estêvao Coelho Teixeira

Design of a Linear Transconductance OTA using the Open Sky130 Process Design Kit

Sociedade Brasileira De Microeletrônica

(2023) sbmicro.org.br
doi: 10.5281/zenodo.10646550

Faculdade de Engenharia, Universidade Federal de Juiz de Fora, Brazil

Abstract: This paper describes the design, layout and simulation of a linear transconductance Operational Transconductance Amplifier (OTA) using the SkyWater 130nm open Process Design Kit (PDK). By using a known source degeneration technique, it is possible to either decrease and linearize the transconductance of the OTA for a wider range of input voltages, making it proper for use on Gm-C filters. Only open source tools, suited for the Sky130 PDK, were used in this design, showing the applicability to analog designs.

Fig: Linear OTA Structure: (a) Complete circuit, with source degeneration resistors;
(b) Alternative source degeneration triode MOSFETs; and its GDSII layout, with identification of some relevant parts: (A) differential pair; (B) source-degeneration resistors; (C) biasing transistors.

Acknowledgment: This work is result from a scientific initiation project covered by the VI VIC 2022/2023 Program, by PROPP/UFJF.

[paper] Systematic approach for IG-FinFET amplifier design using gm/Id method

Alireza Hassanzadeh and Sajad Hadidi

Systematic approach for IG-FinFET amplifier design using gm/Id method

Analog Integrated Circuits and Signal Processing (2021)

https://doi.org/10.1007/s10470-021-01917-9

EE Department, Shahid Beheshti University, Tehran, Iran

Abstract: In this paper, a systematic approach has been used to apply gm/Id method for the design of Independent Gate (IG) FinFET amplifiers. The design of high-performance amplifiers using gm/Id method has been successfully applied to nanometer devices. IG-FinFETs have been widely used in digital circuit implementations. However, the application of IG-FinFETs in analog circuits is limited and brings many advantages including low power, low voltage operation of transistors. Independent gates of FinFET can receive different voltages that facilitate low voltage operation of the circuit. Simulation-based gm/Id method has been applied to IG-FinFET transistors and a systematic methodology has been developed for the design of IG-FinFET amplifiers. The Berkeley BSIM-IMG 55 nm technology parameters have been used for HSPICE simulations. The designed amplifier has a DC gain of about 45 dB while consuming 6.5 µW from a single 1 V power supply.

Fig: gm/Id vs. normalized Id(Vbg)