Design of a Low-Power Universal Gm-C Filter in Sub-Threshold Region

Subject Areas : Renewable energy

Mohammad Aghaei Jeshvaghani ¹ , Mehdi Dolatshahi ²

1 - MSc /Najafabad Branch, Islamic Azad University
2 - Assistant Professor /Najafabad Branch, Islamic Azad University

Received: 2012-09-30 Accepted : 2013-09-09 Published : 2013-11-01

Keywords: Inverter, CMOS, Gm-C, Universal Filter, sub-threshold,

Abstract :

In this paper, a second order universal filter with the ability of electronically tuning central frequency (ω0) and quality factor (Q), based on the inverter as transconductance block which realizes multi-mode responses (voltage, current, transconductance, transresistance) in sub-threshold region, is presented. Biasing transistors in sub-threshold region, reduces the power consumption of the proposed filter and the grounded capacitors are used to reduce the parasitic effects which is another advantage of the proposed filter circuit. Furthermore, low sensitivity of the performance of the proposed filter to the values of gmi , Ci is considered as another advantage of the proposed circuit. In addition, realizing the proposed filter based on the inverter circuit leads to a reduced value of layout area as well as power consumption. Finally, the proposed filter performance is simulated in HSPICE using 0.18 µm (LEVEL49) CMOS technology parameters. As it is shown in the paper, the proposed filter consumes only 64.69 nW power in a ±0.3V supply voltage.

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