Compact sub-hertz ota-c filter design with interface-trap charge pump

A. Becker-Gomez, U. Cilingiroglu, J. Silva-Martinez
2003 IEEE Journal of Solid-State Circuits  
Single-ended and differential operational transconductance amplifier (OTA) configurations are biased with MOSFET interface-trap charge-pumping (ITCP) current generators to achieve very low transconductances for tunable sub-hertz operational transconductance amplifier-capacitor (OTA-C) filter implementation. This paper reviews the basics of ITCP current generation and presents the transconductors and the OTA-C filter configurations based on these transconductors. One of the filters is a low-pass
more » ... with an experimentally determined lowest cutoff frequency of 0.18 Hz, and the other is a fully differential bandpass with individually tunable lower and upper cutoff frequencies measured down to 0.3 Hz. The former has one 15-pF filter capacitor, and measures 0.0346 mm 2 , whereas the latter contains four such capacitors and occupies 0.188 mm 2 silicon. Experimental evaluation also includes offset, harmonic distortion, and noise performance.
doi:10.1109/jssc.2003.811981 fatcat:mtzfpuyrsrcmnkhzw6q4kjjoqe