A Current Amplifier Circuit and Control Strategy Based on FPGA

With the extensive application of electric vehicles, energy storage systems and other power electronic equipment, the research on large capacity controllable current source will be an important direction in the future. This paper proposes controllable current source controlled by a full digitally hysteresis current based on field programmable gate array(FPGA), in which the single phase full bridge topology is adopted as the main circuit of current source. The two levels and three levels hysteresis current control strategies are analyzed and compared with the platform of PSCAD/EMTDC. The user defined component was adopted to realize the two difference control strategies with fortran language program. The simulation results verified that the two levels hysteresis current control strategy is much more fit for the controllable current source. Finally, a prototype is designed and fulfilled and it is controlled by the digitally controller with FPGA. The hysteresis current control is realized by FPGA controller with VHDL programming. The experimental results show that the researched hysteresis current control technology is effective for the current amplifier

Design and Simulation of a Capless Low Drop Out Voltage Regulator

Portable electronic devices mostly used battery as their primary source for operation hence longer running batteries or Power resources or vital for any portable device need for stable voltage supplies have led to the development of low dropout voltage regulators low dropout regulators provide stable regulated output voltage in various operating conditions which makes it useful in portable devices that design of high performance and stable low dropout voltage regulator is a challenge nowadays with decreasing device size and increasing power densities. The proposed circuit used a 5pack architecture of error amplifier. This paper proposes the study of behavior of the LDO voltage regulator with internal capacitors i.e., capless. The regulated voltage of 1.8V is obtained using the typical power supply of 2.2V obtained dropout voltage of 400mv with the delay of 12.77micro sec, power consumed 1.816W. The proposed design produced DC gain of 31.77db,with the load current variation of 0 to 20mA. The capless LDO architecture is verified in the Cadence 180nm technology. The architecture provides a stable gain and plot for both Temperature and Load Variations. The stability issues are overcome using the compensation techniques which uses a current amplifier and a capacitor in the differentiator configuration. The current amplifier implemented uses current mirror with current copying ratio of unity.

Battery Pot Plants with Magnets and Adjacent Balloon as Substitutes for Light

In a future of clean technologies and innovations, it is important with knowledge of new Power sources in terms of the impact on living plants and surrounding life. Organic battery plants with electric components are constructed and analysed. The purpose is to study how illumination i.e. light energy, can be replaced with electricity and matter. The novelty of the paper is the constructions; namely a Balloon capacitor next to a current amplifier in the lines of a pot battery with a plant that should prosper, and the related analysis. Also certain aspects of small magnetic fields alone are invoked. Doi: 10.28991/HEF-2021-02-02-05 Full Text: PDF

Photoelectric Detection System and Machine Learning Recognition Method of Its Detection Images

In the photoelectric detection system, the photoelectric detector can convert the optical signal to be measured into a current signal, and the current amplifier transforms the current signal output by the detector into a voltage signal for amplification. In this study, the photo-multiplier tube (PMT) is selected as the photoelectric detector. Compared with other photoelectric detectors, it can obtain higher internal gain, higher sensitivity, and better response performance. The current amplifier is prepared by pre-amplifier and voltage amplifier. In order to capture photoelectric signals well, a large-format scanning system is set up to design each component module, control module, and host computer module of the system. Besides, a machine learning-based algorithm is proposed, namely semi-supervised manifold image recognition algorithm, which is used for identify photoelectric detection images. In the test process, the printed circuit board (PCB) and sapphire material are firstly used as the substrate of the current amplifier, and their influences in the circuit are compared. The peak value of the output noise of each substrate circuit is around 2.8 mV when the input of the current amplifier is short-circuited. Then, the signal gain and signal bandwidth of the photoelectric detection system remain stable when there is no optical signal input. During the process of changing the system signal gain ratio, the noise output of the system is the lowest when the voltage of PMT is 0.50 V and the current amplifier gain is set to 2.2 × 105 V/A. The proposed recognition algorithm can identify different types of targets well. After the image is projected into a two-dimensional space by the algorithm, the distance between classes increases, and the targets in the class promote aggregation, thereby enhancing the identify-ability between samples.

A CMOS Image Sensor with a Novel Passive Pixel Array and High Precision Current Amplifier for a Compact Digital X-ray Detector

An active pixel sensor (APS) in a digital X-ray detector is the dominant circuitry for a CMOS image sensor (CIS) despite its lower fill factor (FF) compared to that of a passive pixel sensor (PPS). Although the PPS provides higher FF, its overall signal-to-noise ratio (SNR) is lower than that of the APS. The required high resolution and small focal plane can be achieved by reducing the number of transistors and contacts per pixel. We proposed a novel passive pixel array and a high precision current amplifier to improve the dynamic range (DR) without minimizing the sensitivity for diagnostic compact digital X-ray detector applications. The PPS can be an alternative to improve the FF. However, size reduction of the feedback capacitor causes degradation of SNR performance. This paper proposes a novel PPS based on readout and amplification circuits with a high precision current amplifier to minimize performance degradation. The expected result was attained with a 0.35-μm CMOS process parameter with power supply voltage of 3.3 V. The proposed PPS has a saturation signal of 1.5 V, dynamic range of 63.5 dB, and total power consumption of 13.47 mW. Therefore, the proposed PPS readout circuit improves the dynamic range without sacrificing the sensitivity.

The CMOS Highly Linear Current Amplifier with Current Controlled Gain for Sensor Measurement Applications

This paper introduces a new current-controlled current-amplifier suitable for precise measurement applications. This amplifier was developed with strong emphasis on linearity leading to low total harmonic distortion (THD) of the output signal, and on linearity of the gain control. The presented circuit is characterized by low input and high output impedances. Current consumption is significantly smaller than with conventional quadratic current multipliers and is comparable in order to the maximum processed input current, which is ±200 µA. This circuit is supposed to be used in many sensor applications, as well as a precise current multiplier for general analog current signal processing. The presented amplifier (current multiplier) was designed by an uncommon topology based on linear sub-blocks using MOS transistors working in their linear region. The described circuit was designed and fabricated in a C035 I3T25 0.35-µm ON Semiconductor process because of the demand of the intended application for higher supply voltage. Nevertheless, the topology is suitable also for modern smaller CMOS technologies and lower supply voltages. The performance of the circuit was verified by laboratory measurement with parameters comparable to the Cadence simulation results and presented here.

Performance assessment of amplification and discrimination electronic devices for passive neutron measurements

The knowledge of the fissile material mass is a key challenge to enhance radioactive waste management and to ensure a high level of safety in nuclear industry. Data is analyzed according to the principles of the neutron measurement techniques. As proportional counters filled with 3He gas display high neutron detection efficiency and a good gamma-ray discrimination, they are the reference detector for passive neutron coincidence counting. A charge preamplifier or a current amplifier, depending on applications, collects the electric pulse produced by neutron interaction in the 3He gas and a threshold discriminator produces a logic pulse used for neutron counting. This paper describes the performance assessment of different commercially available electronics from Mirion Technologies, Precision Data Technology (PDT), Mesytec, as well as MONACO electronics originally developed by CEA LIST for fission chamber measurements in experimental reactors. Comparative passive neutron measurements are carried out with these electronics at CEA/DEN Nuclear Measurement Laboratory in Cadarache. Overall, PDT and Mesytec electronics show similar detection efficiency as the ACH-NA98 charge amplifier, which is commonly used in our laboratory for such applications. However, MONACO electronics have a lower detection efficiency, similar to Mirion 7820 current amplifier used in specific high-count rate applications. An optimisation of MONACO settings would probably be necessary to adapt to 3He counters instead of fission chambers.