Electronic Tunability and Cancellation of Serial Losses in Wire Coils

Abstract

This work presents a novel methodology to adjust the inductance of real coils (electronically) and to cancel out serial losses (up to tens or even hundreds of Ohms in practice) electronically. This is important in various fields of electromagnetic sensors (inductive sensors), energy harvesting, measurement and especially in the instrumentation of various devices. State-of-the-art methods do not solve the problem of cancellation of real serial resistance, which is the most important parasitic feature in low- and middle-frequency bands. In this case, the employment of serial negative resistance is not possible due to stability issues. To solve this issue, two solutions allowing the cancellation of serial resistance by the value of the passive element and an electronically adjustable parameter are introduced. The operational ranges are between 0.1 and 1 mH and 0.1 and 10 mH, valid in bandwidths from hundreds of Hz up to hundreds of kHz. The proposed concepts are experimentally tested in two applications: an electronically tunable oscillator of LC type and an electronically tunable band-pass RLC filter. The presented methodology offers significant improvements in the process of circuit design employing inductors and can be beneficially used for on-chip design, where serial resistance issues can be very significant.

Grounded synthetic series lossy inductor simulator circuits employing single current differencing buffered amplifier

“…Previously, researchers have reported various techniques to electronically control the inductance and extend the tunability range of synthetic inductance. [55][56][57] It is worth mentioning that the both the proposed circuits presented in Figure 2 offer electronic tunability of inductance, allowing for dynamic adjustments by replacing the grounded resistor R 2 with MOS VCR, as demonstrated in Figure 13. This modification provides an additional degree of freedom in controlling the inductance value, thus, enhancing the versatility and adaptability of the circuits for different applications.…”

“…It is well known that the electronic tunability of inductance is beneficial from the viewpoint of enabling dynamic adjustments to the circuit's behavior, facilitating versatile and adaptive applications in various electronic systems. Previously, researchers have reported various techniques to electronically control the inductance and extend the tunability range of synthetic inductance 55–57 . It is worth mentioning that the both the proposed circuits presented in Figure 2 offer electronic tunability of inductance, allowing for dynamic adjustments by replacing the grounded resistor R 2 with MOS VCR, as demonstrated in Figure 13.…”

Design and Verification of a New Universal Active Filter Based on the Current Feedback Operational Amplifier and Commercial AD844 Integrated Circuit

“…In electrical circuits and systems, filters play an essential role in sensors and signal processing and have received considerable attention in recent years because signals acquired through sensing elements must be filtered out of external noise using filters [1][2][3][4][5][6]. The technical literature [7] describes a conceptual scheme for sensing applications in phase-sensitive detection technology, where two low-pass (LP) filters are used to select the frequency range and eliminate out-of-band noise from the sensor device signal.…”

Two New and Improved Electronically Adjustable Voltage-Mode Multifunction Biquadratic Filters With Independent Control of Band-Pass, High-Pass, and Low-Pass/Regular Notch Filter Gains

“…ABBs have been published in the open technical literature [1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15], [16], [17], [18], [19], [20], [21], [22]. VM multifunction biquadratic filters composed of various highperformance ABBs, such as voltage differencing buffered amplifier (VDBA) [23], [24], [25], [26], current feedback amplifier (CFA) [27], [28], [29], [30], [31], [32], differential difference transconductance amplifier (DDTA) [33], voltage differencing differential difference amplifier (VDDDA) [34], voltage differencing differential input buffered amplifier (VD-DIBA) [35], [36], operational transconductance amplifier (OTA) [37], [38], [39], and LT1228 [40], [41], [42], [43], [44], can be found in the open literature and play an important role in various electronic systems.…”