Title :
Modified Charge Amplifier for Stray Immune Capacitance Measurements
Author_Institution :
Sch. of Eng. & Digital Arts, Univ. of Kent Canterbury, Canterbury, UK
Abstract :
It is shown theoretically and by experimentation that the ac stray immune capacitance meter based on the charge amplifier circuit can be modified to reduce the effects of the parasitic capacitance across the feedback capacitor. This is achieved by simply introducing a unity gain buffer amplifier within the circuit loop.
Keywords :
buffer circuits; capacitance measurement; capacitive sensors; capacitors; feedback amplifiers; AC stray immune capacitance measurement; AC stray immune capacitance meter; circuit loop; feedback capacitor; modified charge amplifier circuit; parasitic capacitance effect reduction; unity gain buffer; Bandwidth; Capacitance measurement; Capacitors; Immune system; Impedance; Parasitic capacitance; Capacitance measurement; capacitive sensor; charge amplifier; operational amplifier; parasitic capacitance; parasitic capacitance.;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
DOI :
10.1109/TIM.2014.2298673
