A Linearly Tuneable Ultra Low Power CMOS transconductor with its application to Gm-C filters

A fully CMOS gm block for low voltage, low power, and wide tuning range is presented in this paper. The relative tuning range of 25 is achieved in this transconductor while only consumes 318 μW with 1.2 V supply voltage in TSMC 0.18 μm CMOS process. The wide tuning range transconductor would be appropriate for multi-mode direct conversion receivers. This wide tuning range transconductor is used in the third order channel selection Butterworth filter to show a good tuning range from 500KHz to 10 MHz which covers several communication standards, such as Bluetooth (650 kHz), cdma2000 (700 kHz), Wideband CDMA (2.2 MHz), IEEE 802.11a/g (10 MHz). The wide tuning range has been achieved without using switchable components or programmable building blocks. It is achieved by changing the bias current.