A single-ended CMOS chopper amplifier for 1/f noise reduction of n-channel MOS transistors

作者：Mars Kamel^*; Kawahito Shoji

来源：IEICE Electronics Express, 2012, 9(2): 98-103.

DOI：10.1587/elex.9.98

• chopping
• low noise
• 1/f noise reduction

This paper describes a single-ended CMOS chopper amplifier for 1/f noise reduction of n-channel MOS transistors and its application to a low-noise high-gain switched-capacitor (SC) amplifier for sensor interface circuits. Since the chopping is used inside of the operational transconductance amplifier (OTA), this amplifier can be used for high output impedance sensors. To investigate the effect of the proposed chopping technique, a test chip was fabricated using 0.25 mu m mixed-signal CMOS process. The total input-referred noise is greatly reduced by using a high chopping frequency of 256 kHz to 20 mu V-rms from 295 mu V-rms without chopping.

• 出版日期2012-1-25