Title :
Nauta OTA in a second-order continuous-time delta-sigma modulator
Author :
Nur Irfansyah, Astria ; Long Pham ; Nicholson, Andrew ; Lehmann, T. ; Jenkins, J. ; Hamilton, Tara J.
Author_Institution :
Sch. of Electr. Eng. & Telecommun., Univ. of New South Wales, Sydney, NSW, Australia
Abstract :
This paper discusses and shows the use of Nauta operational transconductance amplifiers as integrator elements in a second-order continuous-time delta-sigma ADC. The structure is studied in order to take advantage of its potentially high bandwidth operation and simple inverter-based structure for wide output voltage range in current and future CMOS process. The second-order continuous-time delta sigma modulator circuit is implemented in CMOS 65nm, with simulation results showing that 63.29-dB SFDR, and an SNDR of 58.11-dB or 9.36 effective number of bits are achieved, with a signal bandwidth of 8 MHz and sampling frequency of 1.024 GHz. Challenges related to implementation issues and their trade-off are discussed.
Keywords :
CMOS analogue integrated circuits; UHF amplifiers; analogue-digital conversion; delta-sigma modulation; logic gates; operational amplifiers; ADC; CMOS process; Nauta OTA; bandwidth 8 MHz; frequency 1.024 GHz; integrator elements; inverter-based structure; operational transconductance amplifiers; second-order continuous-time delta-sigma modulator; size 65 nm; Bandwidth; CMOS integrated circuits; CMOS process; Inverters; Modulation; Resistance; Transconductance;
Conference_Titel :
Circuits and Systems (MWSCAS), 2014 IEEE 57th International Midwest Symposium on
Conference_Location :
College Station, TX
Print_ISBN :
978-1-4799-4134-6
DOI :
10.1109/MWSCAS.2014.6908548
