A Low-Power Programmable Bandpass Filter Section for Higher Order Filter Applications

We present a programmable, continuous-time bandpass filter that is extremely compact, power efficient, and can cover a wide range of frequencies (10 Hz-10 MHz). This capacitively coupled current conveyor (C ⁴) has a second-order bandpass transfer function and is capable of being used as a basic bandpass-filter element to create high-order filters. The use of floating-gate transistors helps to ease the difficulties of effectively utilizing G _m-C filters by providing precise, programmable current sources that set the filter´s time constants. Additionally, we provide an algorithmic design approach for constructing these bandpass filters to meet any given specifications. This bandpass filter is ideally suited to large filter-bank applications because of its small size and low-power demands.