Design of CMOS CFOA Based on Pseudo Operational Transconductance Amplifier

A novel design technique employing CMOS Current
Feedback Operational Amplifier (CFOA) is presented. The feature of
consumption very low power in designing pseudo-OTA is used to
decreasing the total power consumption of the proposed CFOA. This
design approach applies pseudo-OTA as input stage cascaded with
buffer stage. Moreover, the DC input offset voltage and harmonic
distortion (HD) of the proposed CFOA are very low values compared
with the conventional CMOS CFOA due to the symmetrical input
stage. P-Spice simulation results are obtained using 0.18μm MIETEC
CMOS process parameters and supply voltage of ±1.2V, 50μA
biasing current. The p-spice simulation shows excellent improvement
of the proposed CFOA over existing CMOS CFOA. Some of these
performance parameters, for example, are DC gain of 62. dB, openloop
gain bandwidth product of 108 MHz, slew rate (SR+) of
+71.2V/μS, THD of -63dB and DC consumption power (PC) of
2mW.

• Hassan Jassim Motlak

• Pseudo-OTA used CMOS CFOA
• low power CFOA
• high-performance CFOA
• novel CFOA.

[1] Ahmed H. Madian, Soliman A. Mahmoud, and Ahmed M. Soliman,
"New 1.5-V CMOS Current Feedback Operational Amplifier", IEEE,
2006, pp. 600-603.
[2] Salvatore Pennisi, "High-Performance CMOS Current Feedback
Operational Amplifier", IEEE Journal, 2005, pp. 1573- 1576.
[3] Hio Leong Chao and Dongsheng Ma, "CMOS Variable-Gain Wide-
Bandwidth CMFB-Free Differential Current Feedback Amplifier for
Ultrasound Diagnostic Applications", IEEE Journal, 2006, pp. 649-652,
[4] G. Giustolisi, G. Palmisano, G. Palumbo and S.Pennisi, "High-Drive
CMOS Current-Feedback Opamp", IEEE Journal, 1997, pp. 229-232
[5] Jirayuth Mahattanakul and Chris Toumazou, "A Theoretical Study of the
Stability of High-Frequency Current Feedback Op-Amp Integrators",
IEEE Transactions on Circuits and Systems, vol. 43, no.1, January 1996,
pp. 1-12.
[6] Giuseppe Di Cataldo, Alfio Dario Grasso and Salvatore Pennisi, "Two
CMOS Current Feedback Operational Amplifiers", IEEE Transactions
on Circuits and Systems, 2007, pp. 1-5.
[7] Ali Assi, Mohamad Sawan, and Jieyan Zhu, "An offset compensated and
High- Gain CMOS Current-Feedback Op-Amp", IEEE Transaction on
Circuits and Systems, vol. 45, no. 1, January 1998. pp. 85-90.
[8] Aly M. Ismail and Ahmed M. Soliman, "Novel CMOS Current
Feedback Op-Amp Realization Suitable for High-Frequency
Applications",", IEEE Transaction on Circuits and Systems, vol. 47, no.
6, June 2000, pp. 918-921.
[9] S. Selvanayagam and F. J. Lidgey," Wide Bandwidth CMOS Current
Feedback Op Amp for Inverting Applications", IEE Electronics Letters
Journal, 1998, pp. 1-4.
[10] Jieyan Zhu, Mohamad Sawan, and Karim Arabi, "An Offset
Compensated CMOS Current-Feedback Operational Amplifier", IEEE
Journal, 1995, pp. 1552-1555.
[11] G. Palumbo and S. Pennisi, "Current-Feedback Amplifiers versus
Voltage Operational Amplifiers", IEEE Transaction on Circuits and
Systems, vol. 48, no.5, May 2001. pp. 617-623.
[12] M. Djebbi, A. Assi and M. Sawan, "An Offset-Compensated Wide-
Bandwidth CMOS Current-Feedback Operational Amplifier", IEEE
Journal, 2003, pp. 73-76.
[13] Soliman A. Mahmoud, Ahmed H. Madian, and Ahmed M. Soliman,
"Low- voltage CMOS current Feedback Operational Amplifier and its
Applications", pp. 212-218 ETRI Journal, vol. 29, no. 2, April 2007, pp.
655-658.
[14] Ahmed Nader Mohieldin, Edgar Sánchez-Sinencio, and José Silva-
Martínez, "Nonlinear Effects in Pseudo-Differential OTAsWith CMFB",
IEEE Transactions on Circuits and Systems-II: Analog and Digital
Signal Processing, vol. 50, no. 10, October 2003, pp. 762-770.
[15] Phillip E. Allen and Douglas R Holberg, CMOS Analog circuit design,
second edition, New York Oxford University Press, 2004.
[16] Hanspeter Schmid, "The Current-Feedback OTA", IEEE Journal, 2001,
pp.655-658.