A Switched-MOSFET Programmable Low-Voltage Filter

Abstract

This paper describes a digitally programmable low-voltage low-power analogue filter that can be used in hearing-aid circuits. The filter employs the recently introduced switched-MOSFET technique, a sampled-data technique suitable for low supply voltage operation since it avoids the conduction gap of the switches and does not need any dedicated process. The filter was implemented using the DIMES 1.6μm CMOS process and achieves 64 dB dynamic range. The total current consumption, drawn from a 2.2V supply, equals 93μA.