Technique to improve CMRR at high frequencies in CMOS OTA-C filters

• Autorzy: Blakiewicz G.
• Języki publikacji: EN

Abstrakty

EN

In this paper a technique to improve the common-mode rejection ratio (CMRR) at high frequencies in the OTA-C filters is proposed. The technique is applicable to most OTA-C filters using CMOS operational transconductance amplifiers (OTA) based on differential pairs. The presented analysis shows that a significant broadening of CMRR bandwidth can be achieved by using a differential pair with the bodies of transistors connected to AC ground, instead of using a pair with the bodies connected to the sources. The key advantages of the technique are: no increase in power consumption (except for an optional tuning circuit), a small increase of a chip area, a slight modification of the original filter. The simulation results for exemplary OTAs and a low-pass filter, designed in a 0.35 μm CMOS process, show the possibility of broadening the CMRR bandwidth several times.

Słowa kluczowe

EN

common-mode rejection ratio; CMRR; CMOS; OTA; differential pair; OTA-C filters; component mismatch

• Wydawca: Polska Akademia Nauk, Wydział IV Nauk Technicznych
• Czasopismo: Bulletin of the Polish Academy of Sciences. Technical Sciences
• Rocznik: 2013
• Tom: Vol. 61, nr 3
• Strony: 697--703
• Opis fizyczny: Bibliogr. 16 poz., wykr., rys., tab.

Twórcy

autor

Blakiewicz G.

• Department of Microelectronic Systems, Gdansk University of Technology, 11/12 Narutowicza St., 80-952 Gdansk, Poland

Bibliografia

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