Novel CMOS linear OTA using feedback control on common source node

Low distortion CMOS transconductance amplifier

“…Transconductance elements are useful building blocks in analogue signal processing systems, especially in continuous time ® lters and four-quadrant multipliers (Babanezhad and Temes 1985, Seevinck and Wassenaar 1987, Wilson and Chan 1990, Sevenhans and Van Paemel 1991, Raut 1992, Mahmoud and Soliman 1999. Many implementations have been reported in the literature for obtaining highly linear transconductors .…”

“…In addition, the power consumption of these structures is usually limited compared with other realizations. Several techniques have been described to extend the linearity range of the LTP (Nedungadi and Viswanathan 1984, Babanezhad and Temes 1985, Wilson and Chan 1990, Sevenhans and Van Paemel 1991, Kimura 1994. The cross-coupled technique was ® rst proposed by Khorramabadi (1985) ; this properly scales the aspect ratios of the di erential pair and the bias current used.…”

Novel linearization circuit for BiCMOS transconductors used in high frequency OTA-C filters

“…An input of this differential stage is fixed to a value Vs that is a replica of the common-source voltage of M1 and M2. , I The main advantage of this technique is that it afl'ccu nciihcr the frequency response of the integrator (because it acts only on the higher harmonics of the signal avoiding to introducc extrapoles and consequent phase-shifts) nor the common-modc bchaviour [3]. Furthermore the extra power consumption is vcry limited (Ip is only 20pA).…”