A 5.2nV/√Hz noise density third-order FDNR filter for DVB-H mobile-TV receiver

In this paper, noise-shaping gain-filtering techniques which minimize noise over the range of passband filter have been studied. These techniques will be demonstrated by applying it on a part of CMOS mobile-TV receiver. This paper mainly focuses on designing a low pass filter, consisting of two cascaded parts. The first part is Frequency Dependent Negative Resistance (FDNR) based third-order noise shaped pre-filter section, which has DC gain of 80dB, with cutoff frequency of 818KHz and input referred noise voltage power spectral density of 5.2nV/sqrt(Hz). The second part is Asymmetric Floating Frequency Dependent Negative Resistance (AFFDNR) based feedback network, which is a part of instrumentation amplifier. It has DC gain of 20dB, with cutoff frequency of 765KHz and input referred noise voltage power spectral density of 83nV/sqrt(Hz). These two filters depend on CMOS op amp which has DC gain of 82dB, with unity gain bandwidth of 319MHz, phase margin of 61^° and power dissipation of 428μW. This CMOS op amp is designed based on 0.25μm CMOS technology with power supply of ±1.5V.