Title :
Use of chopper-notch modulator in chopper amplifiers for replica images cancellation
Author :
Geusa, Francesco ; Agnes, Andrea ; Maloberti, Franco
Author_Institution :
Dept. of Electron., Univ. of Pavia, Pavia
fDate :
Aug. 31 2008-Sept. 3 2008
Abstract :
A method for cancelling the replica image limiting the chopper stabilization technique is presented. The modulation of the 1/f noise at the chopping frequency and its multiple are conventionally reduced by a low-pass filter and, possibly by a notch filter. The method presented here combines the second chopper and the notch filter by using a simple SC circuit that enables cancelling the replica images. The method just requires a simple local loop for reducing the amplified offset to a reasonable level and this is obtained with a simple modification of the amplifier used in the chopper scheme. Simulation results show the expected benefits.
Keywords :
amplifiers; choppers (circuits); image processing; low-pass filters; modulators; notch filters; chopper amplifiers; chopper stabilization; chopper-notch modulator; low-pass filter; notch filter; replica images cancellation; Capacitors; Choppers; Circuit noise; Circuit simulation; Frequency; Limiting; Low pass filters; Low-frequency noise; Noise cancellation; Noise reduction;
Conference_Titel :
Electronics, Circuits and Systems, 2008. ICECS 2008. 15th IEEE International Conference on
Conference_Location :
St. Julien´s
Print_ISBN :
978-1-4244-2181-7
Electronic_ISBN :
978-1-4244-2182-4
DOI :
10.1109/ICECS.2008.4674916
