An Ultra Low-Power 7th order active-RC LPF for IEEE 802.15.4a standard compliant transceiver

This paper describes an ultra-low power differential 7^th order active-RC low pass filter (LPF). The proposed filter is ready for the use in Impulse-Radio (IR) Ultra-Wideband (UWB) IEEE 802.15.4a standard compliant transceivers. The circuit is composed of three biquadratic and one first order filter sections. The structure of the operational amplifier (op amp) is adopted to ensure high linearity demands of the design. The evaluation of the LPF was done both for the stand alone version and with the cooperation of other transceiver components inside the IR UWB receiver and the transmitter test circuits. The designed LPF can handle the signals with the peak-to-peak amplitude of 680 mV, has corner frequency of 180 MHz and consumes 3.2 mA from 2.6 V supply. The circuit is fabricated in 0.25 μm SiGe:C BiCMOS technology of the IHP. The chip size is 130×430 μm².