First Page

This brief presents a CMOS voltage reference for ultra-low-power applications, such as in implementable medical devices and energy harvesting-based wireless sensor nodes. In these excellent capabilities to reject interference from power sources work low extend survival periods are critical the references. A transistor size-ratio determined current generator with high process independence is implemented by two same-threshold-voltage NMOS transistors, hence obtaining precise an active load....

A low temperature coefficient (TC) and high power supply ripple rejection (PSRR) CMOS sub-bandgap voltage reference (sub-BGR) circuit using subthreshold MOS transistors a single BJT is presented in this brief. The proposed sub-BGR consists of novel complementary-to-absolute-temperature (CTAT) generator based on scaled emitter-base BJT, an improved proportional-to-absolute-temperature (PTAT) stacking <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML"...

Wireless power transfer (WPT) systems are becoming increasingly popular for sub100mW biomedical applications [1] -[5]. Because the received is sensitive to coupling and loading conditions, power/voltage regulations essential achieve stable accurate delivery, fast transient response, high end-to-end (E2E) efficiency, which includes all losses in transmitter (TX), wireless link, receiver (RX). Many existing WPT designs operated open-loop [3] -[5]; or achieved voltage regulation but only RX...

An experiment was carried out to investigate the effect of CFRP, GFRP and BFRP materials on strengthening reinforced concrete slabs. RC slab specimens were tested a steel frame with four supporting edges. They centrally loaded actuator an MTS through plate. The capacity failure mode slabs strengthened different material systems determined compared. A finite element model (using ANSYS program) used for predicting process systems. predicted experimental results are in good agreement.

Two-dimensional (2D) hopper flow of disks has been extensively studied. Here, we investigate ellipses with aspect ratio $\alpha = 2$, and contrast that behavior to the disks. We use a quasi-2D containing photoelastic particles obtain stress/force information. simultaneously measure particle motion stress. determine several properties, including discharge rates, jamming probabilities, number in clogging arches. For both types, size opening, $D$, relative particles, $\ell$ is an important...

In this paper, a current-mode bandgap reference (BGR) circuit with cascode current mirrors and improved frequency compensation for achieving high power supply ripple rejection (PSRR) is presented. By slightly modifying conventional scheme, the PSRR of BGR significantly enhanced. PSRRs two different techniques have been formulated verified. Moreover, design considerations are presented, taking into account critical parasitic capacitor's effect in PSRR. To our knowledge, first time literature...

To overcome the limitations of transient handling capability, current capacity, power efficiency, and density in existing single-inductor multiple-output (SIMO) converters, this article presents: 1) loop response enhancement by fully comparator-based "Buffet-Like" dual-sampling non-linear control; 2) voltage droop suppression hybrid digital LDO (HLDO) attached to each output; 3) efficiency frequency hopping bootstrapped N-type MOSFET (NMOS) output switches; 4) with a smaller than chip...

This article presents a 6.78-MHz wireless power transfer (WPT) system with system-level hysteretic control technique and circuit-level designs for both the receiver (RX) transmitter (TX) chips. The proposed achieves RX local voltage regulation TX global without using any off-chip components (e.g., MCU, DAC, or various controllers decoders) nor current sensing coils, which were required in previous works. A higher light-load efficiency instant load-transient response are also achieved because...

We consider jamming that occurs for the flow of dry granular materials from a hopper as outlet size, D, is reduced relative to particle d. propose and test model based on simple idea probability short time, dt, constant, τ. This leads prediction surviving until time t without an exponentially decaying function, Ps(t) = exp(−t/τ). The important physical question what determines τ? Experiments date have confirmed exponential character survival probability. Work in progress characterizes τ(D,...

Galvanically isolated voltage regulators (GIVRs) are widely used in industrial automation, electric vehicles, and medical devices to deliver power low-voltage circuits across domains ensure human safety device reliability hazardous environments. Traditional bulky transformer-based GIVRs can 2W output with 80% peak efficiency [1]. However, transformers relatively expensive, their size limits the overall physical of system from being further minimized. Inductive using micro have been...

This article presents a capacitive isolated dc–dc converter with both the receiver (RX) and transmitter (TX) chips designed verified in standard 180-nm CMOS process measurement results. work achieves following features. First, much higher efficiency, by using power links instead of low-quality micro-transformers switching at relatively lower frequency near resonance. Measurement shows 68% peak which is 15% than state-of-the-art miniature designs over almost entire loading range. Second, RX...

A low-power CMOS voltage reference with active-feedback frequency compensation is proposed for power-constrained IoT applications whereby power supply ripple rejection (PSRR) performance critical the survival of devices. The consists MOS transistors operating in sub-threshold region to allow low-voltage and operations. An technique has been used make loop stable improve PSRR a very small capacitor while allowing relatively large output capacitor. circuit fabricated standard 0.18-μm process....

Summary An amplifier‐offset‐insensitive complementary metal‐oxide‐semiconductor (MOS) voltage reference (CVR) circuit with high power supply ripple rejection (PSRR) is presented. Due to the novel structure of employing subthreshold MOS transistors, proposed CVR can suppress direct current offset effects internal amplifier. Design considerations in optimizing and area consumptions improving PSRR are The implemented a standard 0.18 μm process. Measured results show that run down‐to 0.9 V...

This paper presents an NMOS pseudo-digital low-dropout (PD-LDO) regulator that supports low-voltage operation by eliminating the amplifier of analog LDO. The proposed control loop consists a latched comparator, 2X charge pump and RC network. It detects output voltage provides continuous gate signal for power transistor charging discharging Fast transient response is achieved due to source follower structure NMOS, with small capacitor occupied chip area without consuming large quiescent...

This article presents a four-phase current-mode hysteretic-controlled DC–DC buck converter with fixed-frequency double-adaptive-bound (DAB) control. In prior designs, there exists undesired output DC error caused by control loop delays and mismatches between the RC current sensing network resistance (DCR) of power inductor. Circuit delay is also an obstacle in achieving higher switching frequency multi-phase operation. To address these issues, ratioed digital calibration are proposed. reduce...

3-Level Single-Inductor Multiple-Output (SIMO) buck converter is introduced in [1] to provide multiple outputs sharing one inductor save cost while taking advantage of topologies. Linear voltage-mode PWM control was used [1], which also what most single-output converters used. It intuitive generate matching duty-cycles (D1 and D2) for the 2 pairs switches by having error amplifier (EA) cutting interleaved ramps. However, linear has small-signal bandwidth limitation, even more challenging...

Galvanically isolated DC-DC converters are gaining more attention in the industry due to increasing demands automotive, industrial, powerline, and medical applications. They widely used provide protection between different domains while being able transmit power through barrier. Traditional discrete solutions can watt-level with 70-80% efficiency, however, use of bulky transformers becomes primary bottleneck be further miniaturized package-level. Recently, emerging research both academia has...

This article introduces a small form-factor single-link multiple-output (SLiMO) isolated dc–dc converter design. The proposed design provides two regulated voltage rails with single low-cost standard flexible printed circuits (FPCs)-based micro-transformer 6 mm diameter and 0.13 thickness, achieving both local regulation at the secondary side global power across barrier primary side. A digital discrete frequency control is introduced as scheme for regulation, current-rotation-based of active...

Multiphase DC-DC converters have been widely used to deliver more power efficiently with smaller ripples and faster large-signal dynamic responses [1]–[5]. In terms of closed-loop voltage regulation, traditional linear PWM control has limited small-signal bandwidth, which is further compromised ensure stability at different loading conditions PVT LC variations. Non-linear control, such as hysteretic does not bandwidth limitations nor concerns, thus can potentially achieve a performance....

An NMOS LDO regulator using a dynamic replica to significantly improve the regulation precision is presented. By sensing load current and dynamically adjusting current, power transistor biased properly without compromising all-condition stability of classical fixed-replica regulator. The proposed implemented in 0.18-μm CMOS process, occupying an active chip area 0.039 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . With 1.2 V input...