Title :
Low-power MOS integrated filter with transconductors with spoilt current sources
Author :
van de Gevel, M. ; Kuenen, J.C. ; Davidse, J. ; Roermund, A.H.M.
Author_Institution :
Dept. of Electr. Eng., Delft Univ. of Technol., Netherlands
fDate :
10/1/1997 12:00:00 AM
Abstract :
It is shown that an MOS weak-inversion differential pair can be linearized considerably by replacing the tail current source with a MOSFET biased in the weak-inversion triode region. Calculations show that the transconductance can be kept constant to within +5%/-0% for input voltages up to 130 mV. This linearized differential pair is used in a third-order transconductance-C bandpass filter with 18 Hz and 142 Hz cutoff frequencies, which draws 4.9 nA from a 1.8-V supply. Its dynamic range is 62 dB and its active area is 0.5 mm2
Keywords :
MOS analogue integrated circuits; active filters; band-pass filters; constant current sources; 1.8 V; 142 Hz; 18 Hz; 4.9 nA; MOSFET; active area; dynamic range; linearized differential pair; low-power MOS integrated filter; spoilt current source; third-order transconductance-C bandpass filter; transconductor; weak-inversion triode; Active filters; Band pass filters; Differential amplifiers; Equations; Low voltage; MOSFET circuits; Resistors; Tail; Transconductance; Transconductors;
Journal_Title :
Solid-State Circuits, IEEE Journal of
