A CMOS Low Power Current-Mode Polyphase Filter

A new CMOS polyphase filter based on current followers is presented. Adoptions of such relatively simple building blocks and a filter structure employing minimum number of active elements, have lead to low power solution. The proposed filter is used to construct a 6(th)-order polyphase fully differential filter suitable for Bluetooth low-IF receiver. Experimental results show that the proposed design satisfies the selectivity and dynamic range specifications of Bluetooth while consuming relatively low power of 2.38mW.