Title :
Zero CVF input current switched-capacitor instrumentation amplifier
Author :
Willis, David J. ; Jost, Randy J.
Author_Institution :
Utah Design Center, AMI Semicond., American Fork, UT
Abstract :
Most existing switched-capacitor amplifiers require current from the source to charge the input capacitor. This can cause errors when the source driving the amplifier has a large output resistance. In addition, nonideal parameters in opamps can cause errors. In the literature, circuits are found that can reduce the input current or reduce the errors of the opamp. However, none reduce both. This paper presents a new switched-capacitor amplifier topology that employs a pre-charge phase to reduce input current from the source and at the same time reduce errors due to the opamp. The design can be configured as a fully differential instrumentation amplifier with near infinite input resistance
Keywords :
instrumentation amplifiers; network topology; operational amplifiers; switched capacitor networks; Zero CVF instrumentation amplifier; differential instrumentation amplifier; infinite input resistance; input capacitor; input current instrumentation amplifier; input current reduction; opamps; output resistance; precharge phase; switched-capacitor amplifier topology; switched-capacitor instrumentation amplifier; Circuit noise; Circuit topology; Differential amplifiers; Instruments; Noise reduction; Semiconductor device noise; Semiconductor optical amplifiers; Switched capacitor circuits; Switching circuits; Voltage;
Conference_Titel :
Circuits and Systems, 2005. 48th Midwest Symposium on
Conference_Location :
Covington, KY
Print_ISBN :
0-7803-9197-7
DOI :
10.1109/MWSCAS.2005.1594336
