CMOS Analog Filter Design for Very High Frequency Applications

Abstract

A design strategy for the synthesis of high-selectivity/low-order analog filters in Complementary Metal-Oxide-Semiconductor (CMOS) technology for very high frequency (VHF) applications is presented. The methodology for the reconstitution of a given transfer function by means of Signal Flow Graphs (SFG) manipulation in canonical form is proposed leading to a fully differential g m -C biquad filter. As a practical example, the design of a notch filter intended to suppress interferers in the lower sideband (400 MHz) of the Medical Implant Communication Service (MICS), in single-poly, 6-metal layers; Mixed-Signal/RF 0.18 µm CMOS technology is realized. To compare the performance of the proposal with some other solution, the design of a 7th order elliptic notch filter based on Frequency Dependent Negative Resistors (FDNRs) was also accomplished. The attained simulation results prove that the proposal is competitive compared to the FDNR solution and some other state-of-the-art filters reported in the literature. The most salient features of the proposed notch biquad include: the selectivity, whose value is comparable to that of a 7th order elliptic approach and some other 3rd order filters; a high-frequency operation without resonators; linearity, with a +15 dBm I I P 3 ; a reduced form factor with a total occupied area of 0.004282 mm2 and mostly a low design complexity.

A Low Power Analog Integrated Fractional Order Type-2 Fuzzy PID Controller

“…The MIN/MAX operators are widely used in a variety of applications within nonlinear signal processing tasks or control theory. Various methods have been suggested in the literature, encompassing Winner-Take-All or Loser-Take-All circuits alongside comparators, related to Fuzzy theory [81,82]. The implemented design of the MIN/MAX operator, as proposed in [83] opts for systems with only two inputs.…”

Electronically Controlled Power-Law Filters Realizations

“…In addition, the OTA-C filter structures have capability of monolithic implementation, reducing the cost of mixed-signal systems. On the other hand, the effect of parasitics, the changes of transconductance with frequency variations, and the reduction of linearity which originated from the small-signal nature of the transconductance are the drawbacks of the employment of these active elements [24]. The OTA-C implementation of ( 26) is depicted in Figure 3b, where the realized time constants are given by: The calculation of the values of coefficients K i , (i = 0, 1, .…”

On Systematic Design of Fractional-Order Element Series

“…It may be noted that for , the fractor defined by ( 1 ) becomes resistor, capacitor, or inductor, respectively. For , the fractor ( 1 ) can be used to describe higher-order immittances, e.g., the frequency dependent negative resistor (FDNR), finding their application in a higher-order frequency filter design [ 48 , 49 ].…”