## 4 Conclusions  
In this work, a wideband reconfigurable integrated LPF for 5G NR compatible SDR solutions was designed and validated. The LPF has programmable bandwidth with 92.8 tuning ratio--from 2.5 MHz to 200 MHz. This is achieved by connecting two overlapping frequency paths that are connected in parallel, both using Active-RC topology. The order of the filter can be configured to realize a 2 nd, 4 th, or 6 th order LPF function, it has built-in PVT compensation with a tuning range of \(\pm\)42% and power management features, which enable optimization of the filter across its entire bandwidth tuning range. The LPF was designed and verified using 65 nm CMOS process, it occupies 0.429 mm\({}^{2}\) and uses a 1.2 V supply. Across the entire 2.5 MHz to 200 MHz bandwidth selection range \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
**Path** & \multicolumn{4}{c}{**Low Frequency Path (LP)**} & \multicolumn{4}{c}{**How Frequency Path (HP)**} \\ \hline \multirow{2}{*}{THD, dB [5]} & \(-105\) & \(-103.7\) & \(-95.1\) & \(-94.16\) & \(-92.3\) & \(-91.74\) & \(-112.4\) & \(-105.5\) & \(-104.4\) & \(-100.1\) & \(-101.2\) & \(-97.39\) \\  & \(-76.95\) & \(-75.7\) & \(-74.75\) & \(-73.57\) & \(-72.11\) & \(-69.85\) & \(-85.63\) & \(-79.06\) & \(-71.64\) & \(-68.04\) & \(-69.22\) & \(-64.55\) \\ \hline NF, dB & 29.65 & 28.34 & 28.62 & 26.9 & 31.83 & 30.48 & 27.78 & 28.95 & 25.87 & 26.05 & 29.7 & 29.74 \\ \multirow{2}{*}{Intg. Noise, \(\mu\)V\({}_{\text{RMS}}\) [6]} & 21.88 & 52.8 & 19.82 & 45.31 & 28.45 & 67.72 & 49.43 & 182.2 & 40.19 & 132.3 & 62.13 & 202.7 \\  & Noise Floor, dBm & \(-80.35\) & \(-72.63\) & \(-78.17\) & \(-70.48\) & \(-78.17\) & \(-70.48\) & \(-73.19\) & \(-62.02\) & \(-75.08\) & \(-64.92\) & \(-71.26\) \\ \multirow{2}{*}{Dynamic range, dB [7]} & 94.26 & 86.54 & 91.18 & 83.87 & 87.96 & 80.28 & 87.24 & 76.07 & 84.89 & 74.71 & 81.06 & 71.02 \\  & 92.2 & 84.48 & 89.23 & 81.92 & 86.02 & 78.34 & 84.34 & 73.17 & 82.15 & 71.97 & 78.35 & 68.28 \\ \multirow{2}{*}{Dynamic range, dB-Hz [8]} & 158.24 & 159.55 & 155.16 & 156.88 & 151.94 & 153.29 & 160.25 & 159.08 & 157.9 & 157.72 & 154.07 & 154.03 \\  & Power, mW & 1.19 & 2.31 & 4.98 & 9.5 & 6.2 & 11.8 & 3.9 & 14.8 & 15.9 & 58.6 & 19.8 & 73.4 \\ \hline \hline \end{tabular}  
* MFB—multiple feedback topology; LAD—ladder topology. 2 LPF.B—Butterworth; LPF-C-B—cascaded Butterworth. 3 Upper numbers with input tone configuration: first at 10%, second at 19% of bandwidth, both tone amplitude \(-10\) dBm; lower numbers with input tone configuration: first at 40%, second at 70% of bandwidth, both tone amplitude \(-10\) dBm. 4 Input tone configuration: first at 150%, second at 250% of bandwidth, both tone amplitude \(-10\) dBm. 5 Upper numbers with \(-10\) dBm input tone: lower numbers with 4 dBm input tone. 6 Integrated from 1 kHz to Bandwidth. 7 Upper numbers at 15,488 value: lower numbers at 1% THD value. 8 P1 abs/(k \(\times\) T \(\times\) Noise Factor) [22].  
\end{table} 
Table 1: \(Cont.\)  
\begin{table} \begin{tabular}{c c c c c c} \hline \hline  & [19]3  & **[24]4  \\ \hline Process & 130 nm CMOS & 28 nm CMOS & 180 nm CMOS & 180 nm CMOS & 65 nm CMOS & 65 nm CMOS \\ Supply, V & 0.6 & 1.1 & 1.8 & 1.8 & 1.2 \\ Tuning ratio & 4 & N/A & 9 & N/A & 92.8 \\  & A-RC & gm-C & A-RC & A-RC & A-RC \\ Topology 1  & C-BQ & - & SK-BQ—cascaded biquard; FKB——follow-the-leader-feedback; MFB—multiple feedback topology; LAD—ladder topology. 2 BPF-CH—bandpass filter, Chebyshev; LPF-B—Butterworth; LPF-C-B—cascaded Butterworth. 3 In-band IIP3 frequencies for 20 MHz were 6 MHz and 7 MHz, for 160 MHz–48 MHz and 56 MHz; Imp. Noise integrated from 1 to Bandwidth; Dynamic range at 1% THD, 4 P1 abs/(k) P1, \(\sigma\)10 MHz and 40 MHz; h-band IIP3 frequencies 10 MHz and 11 MHz, 4 MHz and 41 MHz; SFDR is in dBc, with 40 MHz and 41 MHz, \(-5\) dBm outings; THD is in dBc, with an input tone 10 MHz, 1 dBm, includes up to 5 th harmonics.[ENDFOOTNOTE] \\ \multirow{2}{*}{Inf. Noise, \(\mu\)V\({}_{\text{RMS}}\)  & **[28]6 [ENDFOOTNOTE]** & **This Work 7 ** \\ \hline \hline \end{tabular}