A Bulk-Driven Variable Gain OTA in 180nm CMOS Technology
محورهای موضوعی : Majlesi Journal of Telecommunication DevicesMohammad Anvari 1 , Farshad Babazadeh 2
1 - Department of Electrical Engineering, Bandaraabas Branch, Islamic Azad University
2 - Department of Electrical Engineering, Bandaraabas Branch, Islamic Azad University
کلید واژه: OTA, Transconductance amplifier, VGA, Variable gain amplifier,
چکیده مقاله :
In this paper, an operational transconductance amplifier (OTA) is designed, simulated and configured so that input dynamic range is improved by bulk-driven technique of the input transistors. The bulk-driven structure is used in the proposed OTA to stabilize the transconductance and to achieve a high linearity. By changing the control voltage and the input common-mode voltage, the voltages and currents of the circuit are changed so that the transconductance and the voltage gain are changed linearly. Also, setting a reference voltage in the circuit can greatly reduce the destructive effects of undesired changes in the circuit operation during fabrication process. The proposed OTA is designed in 180 nm CMOS technology and required only 0.5 V supply voltage. The simulation results show the OTA voltage gain is varied from 0 dB to 14.2 dB by changing the control voltage from 0 to 0.5 V. Moreover, the input common-mode voltage of the OTA can be changed in the range of 0.125 to 0.375V and without linear degradation. The proposed OTA is dissipated 250 nW and makes it suitable for low-power applications.
[1] Holleman, Jeremy, Fan Zhang, and Brian Otis. Ultra-low-power integrated circuit design for wireless neural interfaces. Berlin: Springer, 2011.
[2] Liu, Hang, et al. "Cell-based variable-gain amplifiers with accurate dB-linear characteristic in 0.18 µm CMOS technology." IEEE J. Solid-State Circuits 50.2 (2015): 586-596.
[3] Arbet, Daniel, et al. "Low-voltage bulk-driven variable gain amplifier in 130 nm cmos technology." Design and Diagnostics of Electronic Circuits & Systems (DDECS), 2016 IEEE 19th International Symposium on. IEEE, 2016.
[4] Arbet, Daniel, et al. "Variable-gain amplifier for ultra-low voltage applications in 130nm cmos technology." Information and Communication Technology, Electronics and Microelectronics (MIPRO), 2016 39th International Convention on. IEEE, 2016.
[5] Khumsat, Phanumas, Piamsuk Anantaseth, and Pasin Isarasena. "A low-voltage class-AB CMOS variable gain amplifier." Circuits and Systems, 2007.
[6] Thanachayanont, A., and P. Naktongkul. "Low-voltage wideband compact CMOS variable gain amplifier." Electronics Letters 41.2 (2005): 51-52.
[7] Raikos, George, and Spyridon Vlassis. "0.8 V bulk-driven variable gain amplifier." Electronics, Circuits, and Systems (ICECS), 2010 17th IEEE International Conference on. IEEE, 2010.
[8] Ferreira, Luis HC, and Sameer R. Sonkusale. "A 60-dB gain OTA operating at 0.25-V power supply in 130-nm digital CMOS process." Circuits and Systems (ISCAS), 2014 IEEE International Symposium on. IEEE, 2014.
