*Article* **Bridging the Gap between Design and Simulation of Low-Voltage CMOS Circuits †**

**Cristina Missel Adornes \*, Deni Germano Alves Neto, Márcio Cherem Schneider and Carlos Galup-Montoro**

Department of Electrical and Electronics Engineering, Federal University of Santa Catarina, Florianópolis 88040-900, Brazil; deni.alves@posgrad.ufsc.br (D.G.A.N.); m.c.schneider@ufsc.br (M.C.S.); carlos@eel.ufsc.br (C.G.-M.)

**\*** Correspondence: cristina.m.adornes@posgrad.ufsc.br

† This paper is an extended version of our paper published in 2021 IEEE Nordic Circuits and Systems Conference (NorCAS).

**Abstract:** This work proposes a truly compact MOSFET model that contains only four parameters to assist an integrated circuits (IC) designer in a design by hand. The four-parameter model (4PM) is based on the advanced compact MOSFET (ACM) model and was implemented in Verilog-A to simulate different circuits designed with the ACM model in Verilog-compatible simulators. Being able to simulate MOS circuits through the same model used in a hand design benefits designers in understanding how the main MOSFET parameters affect the design. Herein, the classic CMOS inverter, a ring oscillator, a self-biased current source and a common source amplifier were designed and simulated using either the 4PM or the BSIM model. The four-parameter model was simulated in many sorts of circuits with very satisfactory results in the low-voltage cases. As the ultra-lowvoltage (ULV) domain is expanding due to applications, such as the internet of things and wearable circuits, so is the use of a simplified ULV MOSFET model.

**Keywords:** ACM model; MOSFET modeling; circuit simulation; ultra-low voltage
