A Gain-Tunable Output Buffer for Audio-DAC with Common-Mode Output Independent of Gain Variation

2015 ◽  
Vol 24 (07) ◽  
pp. 1550106
Author(s):  
Yuhua Liang ◽  
Zhangming Zhu
Keyword(s):  
Output Voltage ◽  
Building Blocks ◽  
Threshold Current ◽  
Maximum Output ◽  
Output Buffer ◽  
Common Mode ◽  
Current Reference ◽  
Gain Variation ◽  
Output Noise ◽  
The Common

A novel gain-tunable output buffer for audio-DAC is proposed in this paper. With this proposed architecture, the common-mode output voltage can be independent of gain variation. In practical applications, supply voltage might change. With this proposed architecture, the common-mode output voltage could be set separately, to guarantee that it stays in the mid-scale position of the supply. Therefore, the ability of reaching the maximum output swing for the buffer features the proposed architecture. In addition, the threshold current reference is utilized to generate bias currents for the other building blocks. Therefore, it is always located in the source position of the signal chain. Its output noise would be amplified by all the following circuit blocks. To guarantee high-quality performance of the audio-DAC, the output noise of the threshold current reference should be suppressed. In this letter, noise performance of the threshold current reference is analyzed theoretically and improved significantly. Simulation result shows that the integrated noise current of the threshold current reference can be reduced from 0.61 to 0.15 nA when the integral frequency range sweeps from DC to 50 kHz, i.e., a reduction of 75.4% has been achieved.

scholarly journals Carrier-Based Common Mode Voltage Control Techniques in Three-Level Diode-Clamped Inverter

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Pradyumn Chaturvedi ◽  
Shailendra Jain ◽  
Pramod Agarwal
Keyword(s):  
Output Voltage ◽  
Harmonic Distortion ◽  
Comparison Method ◽  
Rate Of Change ◽  
Common Mode ◽  
Multilevel Inverters ◽  
Common Mode Voltage ◽  
Voltage Signal ◽  
Comparable Performance ◽  
The Common

Switching converters are used in electric drive applications to produce variable voltage, variable frequency supply which generates harmful large dv/dt and high-frequency common mode voltages (CMV). Multilevel inverters generate lower CMV as compared to conventional two-level inverters. This paper presents simple carrier-based technique to control the common mode voltages in multilevel inverters using different structures of sine-triangle comparison method such as phase disposition (PD), phase opposition disposition (POD) by adding common mode voltage offset signal to actual reference voltage signal. This paper also presented the method to optimize the magnitude of this offset signal to reduce CMV and total harmonic distortion in inverter output voltage. The presented techniques give comparable performance as obtained in complex space vector-based control strategy, in terms of number of commutations, magnitude, and rate of change of CMV and harmonic profile of inverter output voltage. Simulation and experimental results presented confirm the effectiveness of the proposed techniques to control the common mode voltages.

Tunable balanced to balanced filtering power divider with high common-mode suppression

Frequenz ◽  
2020 ◽  
Vol 74 (7-8) ◽  
pp. 263-270
Author(s):  
Cao Zeng ◽  
Xue Han Hu ◽  
Feng Wei ◽  
Xiao Wei Shi
Keyword(s):  
Return Loss ◽  
High Selectivity ◽  
Power Divider ◽  
Center Frequency ◽  
Differential Mode ◽  
Common Mode ◽  
Mode Suppression ◽  
The Common ◽  
Equal Power ◽  
Good Agreement

AbstractIn this paper, a tunable balanced-to-balanced in-phase filtering power divider (FPD) is designed, which can realize a two-way equal power division with high selectivity and isolation. A differential-mode (DM) passband with a steep filtering performance is realized by applying microstrip stub-loaded resonators (SLRs). Meanwhile, six varactors are loaded to the SLRs to achieve the center frequency (CF) and bandwidth adjustment, respectively. U-type microstrip lines integrated with stepped impedance slotline resonators are utilized as the differential feedlines, which suppress the common-mode (CM) intrinsically, making the DM responses independent of the CM ones. A tuning center frequency from 3.2 to 3.75 GHz and a fractional bandwidth (12.1–17.6%) with more than 10 dB return loss and less than 2.3 dB insertion loss can be achieved by changing the voltage across the varactors. A good agreement between the simulated and measured results is observed. To the best of authors' knowledge, the proposed balanced-to-balanced tunable FPD is first ever reported.

scholarly journals Analytical Modeling of a Doubly Clamped Flexible Piezoelectric Energy Harvester with Axial Excitation and Its Experimental Characterization

Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3861
Author(s):  
Jie Mei ◽  
Qiong Fan ◽  
Lijie Li ◽  
Dingfang Chen ◽  
Lin Xu ◽  
...  
Keyword(s):  
Output Power ◽  
Power Output ◽  
Output Voltage ◽  
Energy Harvester ◽  
Load Resistance ◽  
Engineering Practice ◽  
Maximum Output ◽  
Widespread Application ◽  
Piezoelectric Energy ◽  
Axial Excitation

With the rapid development of wearable electronics, novel power solutions are required to adapt to flexible surfaces for widespread applications, thus flexible energy harvesters have been extensively studied for their flexibility and stretchability. However, poor power output and insufficient sensitivity to environmental changes limit its widespread application in engineering practice. A doubly clamped flexible piezoelectric energy harvester (FPEH) with axial excitation is therefore proposed for higher power output in a low-frequency vibration environment. Combining the Euler–Bernoulli beam theory and the D’Alembert principle, the differential dynamic equation of the doubly clamped energy harvester is derived, in which the excitation mode of axial load with pre-deformation is considered. A numerical solution of voltage amplitude and average power is obtained using the Rayleigh–Ritz method. Output power of 22.5 μW at 27.1 Hz, with the optimal load resistance being 1 MΩ, is determined by the frequency sweeping analysis. In order to power electronic devices, the converted alternating electric energy should be rectified into direct current energy. By connecting to the MDA2500 standard rectified electric bridge, a rectified DC output voltage across the 1 MΩ load resistor is characterized to be 2.39 V. For further validation of the mechanical-electrical dynamical model of the doubly clamped flexible piezoelectric energy harvester, its output performances, including both its frequency response and resistance load matching performances, are experimentally characterized. From the experimental results, the maximum output power is 1.38 μW, with a load resistance of 5.7 MΩ at 27 Hz, and the rectified DC output voltage reaches 1.84 V, which shows coincidence with simulation results and is proved to be sufficient for powering LED electronics.

scholarly journals A New Approach to the PWM Modulation for the Multiphase Matrix Converters Supplying Loads with Open-End Winding

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 466
Author(s):  
Pawel Szczepankowski ◽  
Natalia Strzelecka ◽  
Enrique Romero-Cadaval
Keyword(s):  
Pulse Width Modulation ◽  
Harmonic Distortion ◽  
Simulation Software ◽  
Common Mode ◽  
New Approach ◽  
Matrix Converters ◽  
Load Voltage ◽  
Common Mode Voltage ◽  
The Common ◽  
Open End Winding

This article presents three variants of the Pulse Width Modulation (PWM) for the Double Square Multiphase type Conventional Matrix Converters (DSM-CMC) supplying loads with the open-end winding. The first variant of PWM offers the ability to obtain zero value of the common-mode voltage at the load’s terminals and applies only six switches within the modulation period. The second proposal archives for less Total Harmonic Distortion (THD) of the generated load voltage. The third variant of modulation concerns maximizing the voltage transfer ratio, minimizing the number of switching, and the common-mode voltage cancellation. The discussed modulations are based on the concept of sinusoidal voltage quadrature signals, which can be an effective alternative to the classic space-vector approach. In the proposed approach, the geometrical arrangement of basic vectors needed to synthesize output voltages is built from the less number of vectors, which is equal to the number of the matrix converter’s terminals. The PWM duty cycle computation is performed using only a second-order determinant of the voltages coordinate matrix without using trigonometric functions. A new approach to the PWM duty cycles computing and the load voltage synthesis by 5 × 5 and 12 × 12 topologies has been verified using the PSIM simulation software.

scholarly journals Opposite Triangle Carrier with SVPWM for Common-Mode Voltage Reduction in Dual Three Phase Motor Drives

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 282
Author(s):  
Seon-Ik Hwang ◽  
Jang-Mok Kim
Keyword(s):  
Electromagnetic Interference ◽  
Pulse Width Modulation ◽  
Motor Drives ◽  
Common Mode ◽  
Pwm Inverter ◽  
Common Mode Voltage ◽  
Voltage Vector ◽  
Three Phase ◽  
The Common ◽  
Zero Voltage

The common-mode voltage (CMV) generated by the switching operation of the pulse width modulation (PWM) inverter leads to bearing failure and electromagnetic interference (EMI) noises. To reduce the CMV, it is necessary to reduce the magnitude of dv/dt and change the frequency of the CMV. In this paper, the range of the CMV is reduced by using opposite triangle carrier for ABC and XYZ winding group, and the change in frequency in the CMV is reduced by equalizing the dwell time of the zero voltage vector on ABC and XYZ winding group of dual three phase motor.

Methodology for the Common Mode Analysis

2007 ◽  
Author(s):  
Zdzislaw H. Klim ◽  
Marek Balazinski
Keyword(s):  
Mode Analysis ◽  
Common Mode ◽  
The Common

Liquid encapsulated electrostatic energy harvester for low-frequency vibrations

2012 ◽  
Vol 24 (1) ◽  
pp. 61-69 ◽  
Author(s):  
Ling Bu ◽  
Xiaoming Wu ◽  
Xiaohong Wang ◽  
Litian Liu
Keyword(s):  
Polyvinylidene Fluoride ◽  
Output Voltage ◽  
Energy Harvester ◽  
Low Frequency ◽  
Electrostatic Energy ◽  
Maximum Output ◽  
Flowing Liquid ◽  
Horizontal Vibration ◽  
Low Viscosity ◽  
High Relative Permittivity

This article presents the modeling, fabrication, and testing of liquid encapsulated energy harvester using polyvinylidene fluoride electrets. Unlike harvesters reported in previous literature, this liquid encapsulated energy harvester uses flowing liquid rather than conventional resonating structures to induce variable capacitance and is more suitable for low-frequency applications. Prototypes injected with three types of liquid ( N-methyl-2-pyrrolidone, N, N-dimethylformamide, and glycerin) are tested in horizontal vibration and rotary motion mode, respectively. The results show that N, N-dimethylformamide–injected prototypes display the most desirable performance in horizontal vibration testing at 1–10 Hz due to high relative permittivity and low viscosity, with maximum output voltage of 2.32 V and power of 0.18 µW at 10 Hz. Glycerin-injected prototypes perform best at 0.1–1 Hz rotation due to effective movement and highest permittivity, with maximum output voltage of 11.46 V and power of 2.19 µW at 1 Hz.

Design of a piezoelectric energy conversion based wind generator

2021 ◽  
pp. 002072092110134
Author(s):  
Sibel Akkaya Oy ◽  
Ali Ekber Özdemir
Keyword(s):  
Low Power ◽  
Energy Conversion ◽  
Output Voltage ◽  
Sensor Nodes ◽  
Maximum Output ◽  
Wireless Sensor Nodes ◽  
Wind Speeds ◽  
Wind Generator ◽  
Piezoelectric Energy ◽  
Renewable Energy Generation

This manuscript presents a new experimental wind generator based on piezoelectric energy conversion for low power applications. The aim is to demonstrate an alternative renewable energy generation method for low power applications. The generator has four blades of a propeller equipped with a total of twenty-four (24) thin film piezoelectric transducers (TFPTs). The output voltage is generated using a newly developed circuit topology. The generator was tested at three wind speeds 10 m/s, 14 m/s and 18 m/s, with a maximum output voltage of 10.2 V being produced at a wind speed of 18 m/s. Results show that this generator has promise to be suitable for low power batteryless applications, for example wireless sensor nodes (WSN).

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