A 1.5-V current-mode capacitance multiplier

In this work the problem of obtaining capacitance values higher than those normally integratable and/or provided by capacitive transducers has been investigated. The solution here proposed consists of a capacitance multiplier made up of a current conveyor and a current operational amplifier which allows accurate capacitance factors up to 100 to be achieved. Moreover, thanks to the use of the current mode approach, low supply voltage operations (profitable in portable sensor systems) are obtained. The whole topology has been designed in a standard 0.5-/spl mu/m CMOS technology with a 1.5-V supply voltage and micropower consumption. SPICE simulations show a good agreement with the expected results and confirm an accurate multiplication factor for capacitances higher than 1 pF.