A three-level boost converter enables efficient voltage step-up power conversion with high power density by reducing the inductance and blocking voltage requirements in a conventional boost converter. An auto-capacitor-compensation pulse frequency modulation (ACC-PFM) controller, combining peak and valley current-mode controls, is proposed to resolve the …
Design and analysis of dual-mode digital-control step-up switched-capacitor power converter with pulse-skipping and numerically controlled oscillator-based frequency modulation. IEEE Transactions on Very Large Scale Integration (VLSI) Systems, 21 …
Frequency tracking and amplitude control are essential for piezoelectric transducers. Frequency tracking ensures the piezoelectric transducer operates at the resonant frequency for maximum power output, and amplitude control regulates the mechanical motion of the output. This paper presents a novel driver based on a push–pull inverter for piezoelectric …
Simulation and experimental results indicate that with proper capacitor-current-feedback coefficient, the proposed CCF-PT control method can successfully achieve effective suppression of low-frequency oscillation for the …
Saitama Institute of Technology Oregon State University Switched-Capacitor Track-and-Hold Amplifier with Low Sensitivity to Op-Amp Imperfections Saitama Institute of Technology Oregon State University All of these SC amplifiers were simulated on the transistor
PWM Frequency A frequency or period is specific to controlling a particular servo. Typically, a servo motor anticipates an update every 20 ms with a pulse between 1 ms and 2 ms. This equates to a duty cycle of 5% to 10% at 50 Hz. Now, if the pulse is at 1.5
This paper presents a novel single-phase grid-connected photovoltaic (PV) converter based on current-fed dual active bridge (CF-DAB) dc-dc converter. The proposed converter allows a minimal DC-link capacitor with large voltage variation without low-frequency effect on maximum power point tracking (MPPT). An advanced control system is developed based on the …
At low frequencies, the dielectric losses dominate and decrease as frequency increases. At higher frequencies, the electrode losses dominate and increase as frequency increases. MLCCs have very low ESR compared to other capacitor technologies, making
In this article, the two kinds of PPSs with extremely small storage capacitor are compared in terms of the configuration, operating principle, main components and efficiency, …
This paper presents a retention/ pulse frequency modulation (PFM)/ pulse width modulation (PWM) mode dc–dc buck converter with adaptive zero current detector (AZCD) and spread spectrum clock generation (SSCG) for IoT/Wearable systems. The proposed dc–dc buck converter is capable of handling loads from 10 μA to 20 mA with high efficiency by applying …
AND90061/D 2 This application note presents design considerations of the half−bridge LLC resonant converter employing NCP4390. It includes an explanation of the LLC resonant converter operation principle, designing the transformer and
The point here is, if you need to select a low-ESL capacitor with high self-resonance frequency, you can use a smaller capacitance, and just put multiple capacitors in parallel. The frequency response for a single low-ESL capacitor or multiple identical capacitors in parallel will be the same.
Two issues plaguing the on-time control dc–dc buck converter are the system instability caused by low equivalent series resistance (ESR) output capacitor and the great variation on switching frequency caused by input/output voltage and load current. Without additional external components or integrated clock-controlled circuits and RC filters, the …
This paper puts forward a model to calculate ESR with consideration of the contact status in spray ends. This model shows that ESR at low frequency (∼100 Hz) is more effective to end contact status than at high frequency (10 kHz).Experiments are designed to ...
The LLC resonant converter has been widely used as a DC–DC transformer (DCX) to provide a semi-regulated or unregulated bus voltage. However, due to circuit parameter variations, the switching frequency is usually different from the designed resonant frequency, which results in converter efficiency degradation. To achieve the highest efficiency under …
A fully-integrated switched-capacitor (SC) DC-DC converter that steps down 2.0 V to 0.9 V with a peak efficiency of 80% is implemented in a 0.18 μ m CMOS process. An ultra-low-power voltage-controlled oscillator that generates a wide range of switching frequencies is proposed to extend battery runtime. An efficiency >70% for load currents in the range of 12 μ …
The large capacitance per unit volume of electrolytic capacitors make them valuable in relatively high-current and low-frequency electrical circuits, e.g. in power supply filters for decoupling unwanted AC components from DC power connections or as coupling
Single-phase AC-DC converter for low-frequency pulse load normally requires high capacitance electrolytic capacitors, which reduces the lifetime and may cause reliability …
Application Note 6 V 1.0 2023-10-20 MOSFET fast switching: motivation, implementation, and precautions Fast switching in high-frequency hard-switched topologies 2.1.2 MOSFET package and PCB layout contributions to the switching times Figure 3 (a) shows ...
4 · Don MacArthur explains how capacitor impedance changes with frequency, including the roles of ESR, ESL, and EPR components. He discusses resonance frequencies, filtering applications, and proper capacitor selection for effective noise reduction in electronic circuits.
The interaction between capacitance and frequency is governed by capacitive reactance, represented as XC. Reactance is the opposition to AC flow. For a capacitor: XC = 1/(2πfC) where: Xc is the capacitive reactance in ohms (Ω) f is the frequency in hertz (Hz) C
A capacitor current feedback pulse train (CCF-PT) control technique for switching DC–DC converters is proposed and applied to the control of a buck converter operating in continuous conduction mode (CCM). The …
It can be seen that the ESR and impedance vary with frequency. When the frequency f < 3 kHz, it is in the low-frequency range. When the frequency is between 3 kHz and …
This article present high efficient electromagnetic energy harvesting system for low frequency applications. The proposed circuit is composed of two stages. In the first stage electromagnetic (EM) rectifier uses an improved rectifier structure with active diodes powered internally by a passive ac-dc positive and negative voltage quadrupler. This boost input peak voltage 0.6 V to …
No single control topology is a good fit for all applications. Designers requiring low electromagnetic interference (EMI) and fast load- transient response should consider advanced emulated current mode (AECM) – a new, constant-frequency and inductor-based control
A clock pulse waveform,, is derived from an input clock using a delay element and logic. When is high, is pulled low and capacitor C charges towards input supply through and . When reaches the switching-point of the inverter,, node is pulled low. is already
Low noise: two-stage output filter example Step #1: • Make the second-stage capacitor 4x to 10x bigger than the first-stage capacitor. Choose 100 uF X5R. Step#2 • Choose new resonant frequency – 150 kHz. Rule of thumb (3-5x higher than loop cross-over
This study investigates a phase-locked loop (PLL) controlled parallel resonant converter (PRC) for a pulse power capacitor charging application. The dynamic nature of the capacitor charging is such that it causes a shift in the resonant frequency of the PRC. Using the proposed control method, the PRC can be optimized to operate with its maximum power …
To balance the instantaneous power difference in the pulse load power supply (PLPS), an active capacitor converter (ACC) is adopted to compensate the pulse current. In this paper, to …
In this paper, we propose a fully integrated switched-capacitor DC–DC converter with low ripple and fast transient response for portable low-power electronic devices. The proposed converter reduces the output ripple by …
The output voltage is regulated by controlling the switches with a pulse–width modulator, pulse–frequency modulator, or digital capacitor modulator (DCpM) [14,15,16,17]. The converting power depends on the storage capacity of the passive components as per the relation P L = L · I 2 /2 for the inductor-based converter and P C = C·V 2 /2 for the capacitor-based …
2.2.1 Pole-zero cancellation Case (i) In (), if the output capacitance is zero.The zero output capacitance demands less bias current for the pass transistor .The first non-dominant pole approximately cancels with the LHP zero, so the improved FVF LDO has only one dominant pole and second non-dominant pole, where is independent of the load current.
In a dc pulsed power supply (PPS), its instantaneous output power is pulsed, and its input power is required to be constant. In order to balance the instantaneous power difference, a storage capacitor is usually connected to the output terminal of the PPS. However, the storage capacitor is extremely large when the pulse repetition frequency (PRF) is relatively …
In this paper, a quadruple boost switched-capacitor multi-level inverter is proposed. The proposed structure utilizes a DC source, 11 switches, and a diode to achieve 17-level output ...
Pulse waves, usually 50%, 25%, and 12.5%, make up the soundtracks of classic video games. The term PWM as used in sound (music) synthesis refers to the ratio between the high and low level being secondarily modulated with a low-frequency oscillator
Based on the structure of active capacitor converter, this paper studies the topology and control strategy of a solid state pulse power supply applied to low repetition pulse …
In order to balance the instantaneous power difference, a storage capacitor is usually connected to the output terminal of the PPS. However, the storage capacitor is extremely large when the …
To convert a subthreshold current to a pulse frequency efficiently and predictably, we designed a silicon soma that conserves energy with current feedback and lessens thermal sensitivity with voltage feedback. When the input current charges a capacitor close to the inversion point of an inverter, its short-circuit current wastes energy. To shorten this period, existing designs …
