A CMOS 4.35-mW +22-dBm IIP3 Continuously Tunable Channel Select Filter for WLAN/WiMAX Receivers

• Published in: IEEE journal of solid-state circuits Vol. 46; no. 6; pp. 1382 - 1391
• Main Authors: Oskooei, Mostafa Savadi, Masoumi, N, Kamarei, M, Sjoland, H
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.06.2011; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Channel select filter; Channels; Circuit properties; CMOS; Cutoff frequency; Design. Technologies. Operation analysis. Testing; Electric, optical and optoelectronic circuits; Electrical Engineering, Electronic Engineering, Information Engineering; Electronic circuits; Electronics; Elektroteknik och elektronik; Engineering and Technology; Exact sciences and technology; Frequency filters; G _{\rm m} -C filter; G(m)-C filter; Integrated circuits; Linearity; Local area networks; Power consumption; Receivers; Resistors; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Teknik; Transistors; Tuning; WiMAX; Wireless communication; Wireless LAN; WLAN; Wireless LAN; Input signal; Third order; G; WiMAX; Receiver; WLAN; C filter; Biquad circuit; Channel select filter; Continuous time filters; Cut off frequency; Butterworth filter; Intercept point; Complementary MOS technology; Tunable filter; Electric power consumption; Active filter; Low pass filter; Low-power electronics; Radio communication
• ISSN: 0018-9200; 1558-173X
• DOI: 10.1109/JSSC.2011.2120670

A low-power high linearity CMOS G m -C channel select filter for WLAN/WiMAX receivers in 90-nm CMOS technology is presented. To reduce power consumption a biquad cell with simple architecture is used. A simple but efficient technique is also proposed to improve the linearity of the filter without increasing its power consumption. Coarse and fine tuning techniques are used to tune the cutoff frequency of the sixth-order Butterworth low-pass filter from 8.1 MHz to 13.5 MHz suitable for WLAN and WiMAX applications. The measurement results show an in-band IIP3 of + 22 dBm, an HD3 better than - 40 dB at 470 mV P input signal amplitude, and an input referred noise of 75 nV/√Hz at a power consumption of 4.35 mW from a 1-V supply. The differential filter occupies a chip area of 0.239 mm 2 excluding pads.