A first order 1Hz integrated filter needing no external components is described. It uses an on-chip capacitor of 100pF and a new differential transconductance amplifier which allows direct implementation of very small transconductances by using MOS transistors in their triode region. This furthermore makes the filter cutoff frequency electrically adjustable. The distortion is very low, less than 0.1% at 4Vpp input voltage. Also the signal-to-noise ratio is good, more than 80dB at 0.1% distortion. This is remarkable because the well-known high 1/f-noise level of MOS transistors is particularly severe at the very low frequencies of interest here.
|Title of host publication||Proceedings of the Nineteenth European Solid-State Circuits Conference|
|Publication status||Published - 1993|
|Event||19th European Solid-State Circuits Conference - Sevilla, Spain|
Duration: 22 Sep 1993 → 24 Sep 1993
Conference number: 19
|Conference||19th European Solid-State Circuits Conference|
|Period||22/09/1993 → 24/09/1993|