A Compact Design of DTMOS-Tunable MOSFET-Only Dual-Output Low-Voltage Current-Mode Filter

Abstract

This paper presents compact, low-power, electronically tunable dual-output filters implemented using DTMOS (dynamic threshold MOSFET) in a 0.18 μm CMOS process. The designs utilize intrinsic transistor parasitic capacitances to realize filter responses, eliminating the need for external passive components. Electronic tunability in both low-pass and band-pass outputs is achieved through the dynamic threshold MOSFET technique, allowing operation at a lower supply voltage with fewer components. The low-pass filter's cut-off frequency can be tuned from 237.2 kHz to 141.34 MHz, while the band-pass filter's center frequency ranges from 218.3 kHz to 132.13 MHz. Three filter configurations are proposed to optimize frequency performance. Simulation results using Cadence–Virtuoso show an average power consumption of 0.213 mW at 1.6 V with a 15 pF load capacitor. The proposed filter design is ideal for integration into modern portable and power-sensitive electronic systems due to its wide tuning range, low voltage operation, low power consumption, and compact size.