Active-MOSFET-C single-amplifier biquadratic filters for video frequencies

Author

Schmid, H. ; Moschytz, G.S.

Author_Institution

Inst. for Signal & Inf. Process., Swiss Federal Inst. of Technol., Zurich, Switzerland

Volume

147

Issue

1

fYear

2000

fDate

2/1/2000 12:00:00 AM

Firstpage

35

Lastpage

41

Abstract

The authors show how continuous-time active-RC filters can be implemented in CMOS by replacing all resistors by MOSFETs operating in the linear region. As an example, a 24 MHz active MOSFET-C single-amplifier biquadratic lowpass filter with a pole-Q of 3 implemented in a 0.6 μm CMOS process is discussed. By comparing measurements of a test chip, simulations and calculations, the following conclusion is reached. As long as the specifications for frequency, pole-Q, spurious-free dynamic range and supply voltage lie within certain limits, then active-MOSFET-C single-amplifier biquads (MOSFET-C SABs) are preferable; with respect to chip size and power consumption, compared to multi-amplifier biquads, e.g. integrator-connected biquads. Above these limits, the latter must be used

Keywords

CMOS analogue integrated circuits; RC circuits; biquadratic filters; continuous time filters; current-mode circuits; harmonic distortion; integrated circuit noise; low-pass filters; operational amplifiers; radiofrequency filters; 0.6 micron; 24 MHz; CMOS process; active-MOSFET-C biquadratic filters; biquadratic lowpass filter; chip size; continuous-time active-RC filters; pole-Q; power consumption; single-amplifier biquadratic filters; spurious-free dynamic range; supply voltage; video frequencies;

fLanguage

English

Journal_Title

Circuits, Devices and Systems, IEE Proceedings -

Publisher

iet

ISSN

1350-2409

Type

jour

DOI

10.1049/ip-cds:20000046

Filename

836509