Wide Range High Precision CMOS Exponential Circuit Based on Linear Least Squares Approach

A. Naderi Saatlo, S. Ozoguz

Wide Range High Precision CMOS Exponential Circuit Based on Linear Least Squares Approach

Číslo: 4/2018
Periodikum: Radioengineering Journal
DOI: 10.13164/re.2018.1092

Klíčová slova: Exponential function, new approximation, analog circuit, high precision

Pro získání musíte mít účet v Citace PRO.

Přečíst po přihlášení

Anotace: A new strategy to implement exponential circuit in CMOS technology is presented in this paper. The proposed method is based on the new approximation function optimized by linear least squares approach to extend the output dynamic range. The current mode method is employed for realization of circuits, because of simple circuitry and intuitive topology. Unlike to the some reported circuits which were designed in the subthreshold region, the proposed design operates in the saturation region which provides acceptable bandwidth for the circuit. In order to validate the circuit performance, the post layout simulation results are presented using HSPICE and Cadence with TSMC level 49 (BSIM3v3) parameters for 0.18 μm CMOS technology. The results demonstrate 78 dB output dynamic range with the linearity error less than ±0.5 dB which shows a remarkable improvement in comparison with previously reported works. A bandwidth of 67 MHz, maximum power consumption of 0.326 mW under supply voltage of 1.5 V, and 0.77% error for temperature variations are further achievement of the design.