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In this paper, an inductorless wideband balun-low noise amplifier (LNA) using current source loads, common-mode feedback (CMFB), asymmetric capacitive cross-coupling (CCC) and auxiliary common-source amplifier are proposed to obtain low noise figure (NF) and high gain. The asymmetric CCC boosts the gain and reduces the NF. The CMFB fixes the output to a common mode voltage. RMS detectors are proposed to realize a low-cost built-in self-test (BIST) circuit for measuring the gain of the LNA during its entire lifespan. The proposed balun-LNA is implemented in 0.18 µm CMOS process technology and the performance is studied through post-layout simulations. PVT and Monte Carlo simulations are performed to check for the robustness and yield of the circuit. From these analyses, it is found that the integrated average gain of the LNA obtained with and without the RMS detectors is 19.1 dB and 20.1 dB respectively in the 3 dB-band of 0.18–2 GHz. NF of the LNA in this band is 2.87 dB. The average IIP3, IIP2, and 1 dB compression points of the LNA are (−4.89 dBm, +28.57 dBm, −20.42 dBm) respectively. The proposed LNA dissipates a power of 4.9 mW with a supply of 1.2 V and requires an area of 0.04 mm2. [ABSTRACT FROM AUTHOR]

Capacitors realized using symmetric floating impedance scaling (SFIS) are area efficient. They are preferred for the implementation of fully differential filters for biomedical applications. The SFIS reported in the literature has poor accuracy and lower effective bandwidth. In this paper, a cross coupled symmetric floating impedance scaling (CC-SFIS) with enhanced bandwidth and accuracy is proposed. To evaluate its performance, a 500 pF capacitor is implemented in UMC 180 nm CMOS technology with a base capacitor (C b) of 10 pF using both CC-SFIS and source follower based SFIS (SF-SFIS). The magnitude and phase of the impedance of the capacitor realized using CC-SFIS and SF-SFIS are obtained through post-layout simulations. CC-SFIS requires 53.68% lower area, 62.39% lower power consumption, and 88% higher accuracy than SF-SFIS. Fully differential 2nd order Butterworth low pass filters with cutoff frequency of 100 Hz are implemented in UMC 180 nm technology using both CC-SFIS and SF-SFIS capacitors. Their performances are evaluated through simulation. From this, it is found that the deviation in the cut off frequency of the filter using CC-SFIS is smaller (2%) compared to that using SF-SFIS (40%) circuit. [ABSTRACT FROM AUTHOR]

A CG-CS wideband balun-LNA using asymmetric capacitive cross-coupling (A-CCC) and an auxiliary current reuse amplifier (ACRA) is reported in the literature. It achieves low noise figure (NF) and high gain at the cost of linearity. To improve the linearity, inductive loads are proposed. However, this is at the cost of increase in chip area. To overcome this problem, a balun-LNA using modified complementary derivative superposition and asymmetric CCC-DS techniques for the ACRA and A-CCC block respectively is proposed in this paper. It dispenses with the inductive loads. The balun-LNAs with and without the proposed linearization are implemented in UMC 180 nm CMOS technology with a supply of 1.2 V and are studied through post-layout simulations. It is found that the proposed LNA has +7.96 dBm increase in average IIP3 compared to the LNA without the proposed linearization. It achieves an average IIP3 of +5.49 dBm with a peak gain of 24.2 dB and minimum NF of 2.18 dB over the bandwidth of 1–3 GHz. The proposed LNA requires an area of 0.3 mm2 and a power of 6.95 mW. [ABSTRACT FROM AUTHOR]