MOSFET Series Research Articles

The Analysis and Research of the Integrated, 30 A MOSFET Gate Driver Dedicated to High-Frequency Applications

This paper presents basic properties and laboratory tests of a commercial integrated high-frequency MOSFET gate driver IXRFD631 operating in the frequency range up to 30 MHz. The MOSFET driver has been tested for two operating states: in the idle state (no load) and at the gate load of a DE275-501N16A series MOSFET transistors. The obtained laboratory results were compared with three other commercial integrated drivers: DEIC420, DEIC515 and IXRFD630 (which are the base structures), and two previous solutions from the author (4xUCC27516 and 8xUCC27526). Additionally, this paper presents the characteristics of power losses and efficiency, measurements of switching and propagation times of the tested gate drivers. Also, this paper presents the output voltage waveforms of the integrated driver IXRFD631 for two operating states. The integrated circuit IXRFD631 of the gate driver is characterized by an efficiency of up to 70% for the tested frequency range, the power losses for two operating states (at idle state—15 W, at gate MOSFET load—43 W) and switching times of 2 ns for an operating frequency of 30 MHz.

Modeling of Threshold Voltage Shift by Neighboring Transistors for Macaroni Channel MOSFETs in Series

Modeling of Threshold Voltage Shift by Neighboring Transistors for Macaroni Channel MOSFETs in Series

Bi-Level Dimmable LED Driver in Refrigerated Display Lighting Systems

Commercial refrigerated display lighting (RDL) systems require LED drivers to provide constant 24 V to multiple LED light bars connected in parallel, each with a built-in current regulator to maintain a constant output brightness. The system uses a passive infrared motion detector to detect approach of people and a dimmer controller to further reduce the power consumption of the LED light bars. RDL system typically requires 100% and 20% only brightness control, so the dimmer controller can be replaced by a 0-10 V dimmable LED driver. By connecting a fixed resistor to the 0-10 V dimming interface, the brightness output can be set to 20%. However, the wiring of this technique is complex. This brief presents a new bi-level dimmable LED driver design that uses an astable multivibrator and totem pole gate driver integrated PWM dimming circuit to achieve a 20 brightness output through a single dimming wire, simplifying system wiring. The driver’s dimming wire is connected to the 24 V output voltage through the AC-powered passive infrared motion detector’s built-in relay, turning on the PWM dimming circuit to generate a 20% duty square wave signal that drives the internal series MOSFET at a frequency higher than 1.25 kHz to avoid LED flicker. This new design has been proven to have the advantages of high efficiency, low cost and easy wiring, and it can replace dimmer controller and 0-10 V dimmable LED driver in RDL applications.

MOSFET series resistance extraction at cryogenic temperatures

A series resistance extraction method proposed recently, which uses multiple drain current versus gate voltage curves at varied drain voltages, was applied to bulk CMOS devices at low temperatures down to 4 K. A moderate reduction of series resistance compared with 300 K was found. Horizontal field dependence of mobility significantly changed with temperature, which was taken into account during the extraction. Anomalous non-linear series resistance was observed at 4 K only for p-channel FETs, suggesting the need for careful source/drain overlap design for low temperature operations.

A robust single device MOSFET series resistance extraction method considering horizontal-field-dependent mobility

A simple MOSFET series resistance extraction method using multiple drain current versus gate voltage curves of a single device is proposed, where mobility modulation by a horizontal electric field (i.e., weak velocity saturation) is taken into account. The method is validated using TCAD, where series resistance determined from internal potential distributions was used as a reliable reference. Measurement results were also obtained which further support the validity of the method.

Comparisons on Different Innovative Cascode GaN HEMT E-Mode Power Modules and Their Efficiencies on the Flyback Converter

The conventional cascode structure for driving depletion-mode (D-mode) gallium nitride (GaN) high electron mobility transistors (HEMTs) raises reliability concerns. This is because of the possibility of the gate to source voltage of the GaN HEMT surging to a negative voltage during the turn off transition. The existing solutions for this problem in the literature produce additional drawbacks such as reducing the switching frequency or introducing many additional components. These drawbacks may outweigh the advantages of using a GaN HEMT over its silicon (Si) alternative. This paper proposes two innovative gate drive circuits for D-mode GaN HEMTs—namely the GaN-switching based cascode GaN HEMT and the modified GaN-switching based cascode GaN HEMT. In these schemes, the Si MOSFET in series with the D-mode GaN HEMT is always turned on during regular operation. The GaN HEMT is then switched on and off by using a charge pump based circuit and a conventional gate driver. Since the GaN HEMT is driven independently, the highly negative gate-to-source voltage surge during turn off is avoided, and in addition, high switching frequency operation is made possible. Only two diodes and one capacitor are used in each of the schemes. The application of the proposed circuits is experimentally demonstrated in a high voltage flyback converter, where more than 96% efficiency is obtained for 60 W output load.

A Modular Switching Position With Voltage-Balancing and Self-Powering for Series Device Connection

Medium-voltage converters, especially those making use of SiC devices, require high common-mode voltage immunity and resilience against associated high dv/dt across multiple isolation barriers. A truly modular and common-mode immune switching position could be beneficial for these applications. The design of a modular switching position is presented here for a series connection of power semiconductors with voltage-balancing and self-powered-gate capabilities. The designs of the voltage-balancing and self-powered circuits are described, followed by simulations and testing of a 3.3-kV switching position formed by two 1.7-kV SiC MOSFETs in series. Testing results demonstrate the ability of the proposed switching position to balance the voltage across series-connected MOSFETs even if the gate signals of the series-connected devices are not perfectly synchronized while powering themselves directly from the OFF-state voltage across them. In addition, a startup circuit for the switching position is proposed and experimentally confirmed.

A compact model of shield-gate trench MOSFET based on BSIM4

Shield-gate trench MOSFET in a low-to-medium voltage range (12－250 V) plays a key role in the power conversion market due to its low power loss caused by the sheild-gate structure. In order to eliminate the faults resulting from the parasitic effects of the device and improve the conversion efficiency, the device model is indispensable in designing a circuit system. In this paper, a compact model of shield-gate trench MOSFET based on BSIM4 is proposed, including the DC model and the capacitance model. In the DC model, the basic MOSFET structure uses BSIM4, and the equivalent resistances of the basic MOSFET in series are divided into three parts. The equivalent resistance model of JFET region is established by using the electric potential difference between both ends for the first time, and the equivalent resistance model of electron diffusion region is also introduced, in order to solve the problem of current error caused by neglecting the source potential of JFET region. The equivalent resistance between drain and JFET region and the equivalent resistance of electron diffusion region both prove to be constant. In the capacitance model based on BSIM4, the model of shield-gate to drain capacitance is added to the model of drain to source capacitance, and the voltage bias between drain and gate in the model of gate to drain capacitance is modified into the potential difference between the node at the end of the gate-drift overlap region and the gate. Poisson equations are used to solve the electric potential of this node. Furthermore, the gate oxide thickness factor <i>k</i><sub>1</sub>, the shield-gate oxide thickness factor <i>k</i><sub>2</sub>, the equivalent length of gate-drift overlap <i>L</i><sub>ovequ</sub> and the equivalent length of shield-gate <i>L</i><sub>SHequ</sub> are introduced to redefine the position of gate and shield-gate, thereby simplifying the Poisson equations and ensuring the smoothness of the potential curve of the node. Comparison of the data from the simulation by using Verilog-A program with the test results from the experimental platform shows that the model simulation results fit well with the test data, Therefore, the proposed model is verified.

Enhancing Short Circuit Capability of 1.2-kV Si IGBT Using a Gate-Source Shorted Si Depletion Mode MOSFET in Series With the Emitter

Short-circuit (SC) capability is a critical requirement for power switches in modern power electronics applications. A tradeoff between on-state voltage drop, switching loss, and SC capability of insulated gate bipolar transistors (IGBTs) is performed by manufacturers. In general, IGBTs optimized with low on-state voltage have poor SC capability compared with those with good SC capability. In this report, a novel method is described to improve the SC capability of IGBTs optimized with low on-state voltage drop by using a gate-source-shorted Si depletion-mode (DM) mosfet connected in series with the emitter. A seven-fold increase in the SC capability of commercially available 1.2-kV IGBTs was achieved at high dc bus voltages with minimal impact on on-state and switching loss performance. The proposed method also provides a sensing voltage signal at the drain of the Si DM- mosfet , which can be used to monitor the on-state current magnitude and to detect SC fault conditions.

Newly Proposed Duty-generator-less Passive Down-conversion Mixer

This study proposed a method for eliminating the 25% duty LO generator (25DLG) and minimizing performance degradation due to the elimination. The advantage of the proposed mixer is that it does not require additional current and area to implement a 25DLG. The switching core of proposed mixer is composed of two MOSFETs in series. The inphase and quadrature-phase LO signals with 50% duty are applied to the gate of each MOSFET. It operates same as conventional mixer using LO signals with 25% duty. The operation range of the proposed mixer is from 500 MHz to 2000 MHz. The Gain and NF (Noise Figure) are 23.6 and 8.9 dB, respectively at 900 MHz. The OIP3 (Output third-order Intercept Point) is 28.6 dBm. The current consumptions of the conventional mixer are 6 mA at TIA from 1.8 V supply and 3.3 mA at a 25DLG and LO buffers from 1.1 V supply. Those of the proposed mixer are only 6 mA at TIA from 1.8 V supply 2.4 mA at LO buffers without 25DLG from 1.1 V supply because it doesn’t need a 25DLG.

In brief

PAGE 1102 Wideband antennas in the lower VHF range are desirable for applications on shipborne systems to enable them to acquire patterns with low elevation angles. A team in China has developed a dual-sleeve wideband monopole antenna with loaded plasma cylinders. It has achieved promising results and is suitable for near omni-directional communications. PAGE 1106 Researchers in Uruguay have presented a bulk-linearised MOSFET with an extended linear range and an equivalent saturation voltage, even in weak inversion, of several hundred mV. Simulation tests of a three series MOSFET and biomedical application circuit demonstrate improved power conversion against existing equipment. Radiation patterns and UAV testing system. PAGE 1137 A harmonic-based power calculation for the dual active bridge topology of bidirectional DC-DC converters has been proposed by researchers in Singapore. The topology is versatile but calculating its power is complex. The team's use of a unified Fourier-based approach reduces the time and complexity of the calculation and is adaptable for other experimental layouts. Bulk-linearisation of the MOS resistor. PAGE 1126 A tri-band bandpass filter, using a conventional stud loaded step impedance resonator (SLSIR) capable of producing three bands of frequencies, has been advanced by researchers in Pakistan. The passbands are independently controllable, and the design provides high selectivity and performance, in accordance with measured and simulated results. Simulated vs calculated power of bridge. PAGE 1141 The need for low-cost and low-power wireless sensor networks has driven researchers in China to design and build a suboptimal Cauchy detector for sensor node line-of-sight (LOS) receiver applications. The proposed detector is notable for its simplicity and robustness, and surpasses the performance of previous Cauchy designs. Fabricated bandpass filter prototype. Robustness of novel suboptimal detector.

Impact of Series Resistance on Bulk CMOS Current Matching Over the 5–300K Temperature Range

This letter presents the impact of source/drain series resistance on the matching of bulk nMOS and pMOS field-effect transistor current over the 5–300K temperature range. A new method to extract series resistance is introduced, and we show experimentally that current variations, considering series resistance, increase as temperature decreases. Moreover, we propose a new approach to calculate the current mismatch based on MOSFET parameters and series resistance. The approach predicts the current variation better than the conventional model over the examined temperatures.

High-frequency composite pulse generator based on full-bridge inverter and soft switching for biological applications

Applying high-frequency pulses to animals for tissue ablation can reduce the number and intensity of muscle contractions. Hence, developing a composite pulse generator is necessary to investigate the mechanism of tumor ablation under high-frequency composite pulses. In this study, a high-frequency and high-voltage composite pulse generator is proposed for such application. This generator combines the technology of full-bridge soft-switching circuit, MOSFET series, and RCD equalization circuit. This generator has the capability of producing composite pulses, in which the center frequencies of the bursts are up to 2 MHz, the inter-burst delay is 0.1–10 s, the pulse width is from 100 ns to 100 μs, the pulse amplitude is ±3 kV, and the rise time is around 30 ns. The parameters satisfy the requirements of the experiments for studying muscle contraction under high-frequency pulses and tumor ablation. The details of the generator’s production of high-frequency composite pulses are provided. An all-solid-state modular design makes the generator compact and reliable. Initial experiments are then conducted to verify the performances of the proposed generator.

3-D Integrated Track-and-Hold Circuit Using InAs Nanowire MOSFETs and Capacitors

This letter presents a vertical integration scheme where track-and-hold circuits, consisting of a MOSFET in series with a metal-insulator-metal (MIM) capacitor, are successfully fabricated along vertical InAs nanowires. The nanowire MOSFET is used as a switch with varying switch resistance, R <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">sw</sub> , as the gate-source voltage, V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">GS</sub> , is varied. The track-andhold circuit operation is verified by a sine wave that is properly evaluated by the circuit. In addition, calculations show that the three-dimensional integration reduces the track-and-hold area a factor of 2, as compared with planar MIM capacitor only. With further nanowire pitch reduction, about ten times area saving is projected.

A Novel Buck–Boost AC–AC Converter With Both Inverting and Noninverting Operations and Without Commutation Problem

This paper proposes a new type of ac–ac converter which can operate as traditional noninverting buck and boost converters, and inverting buck–boost converter as well. The proposed converter uses six unidirectional current flowing and bidirectional voltage blocking switches, implemented by six reverse blocking insulated-gate bipolar transistors (IGBTs) or series mosfet –diode pairs, two input and output filter capacitors, and one inductor. It has no shoot-through problem of voltage source (or capacitor) even when all switches are turned-on, and therefore, pulsewidth modulation dead-times are not needed resulting in high-quality waveforms, and solves the commutation problem without using bulky and lossy RC snubbers or dedicated soft-commutation strategies. It has smaller switching losses because only two switches out of six are switched at high frequency during each half-cycle of input voltage, and it can use power MOSFETs as body diode never conducts, making it immune from mosfet failure risk which otherwise may occur due to poor reverse recovery problem of body diode. The noninverting buck–boost mode of the proposed converter can be used in applications with both step-up and step-down demand, while the inverting buck–boost mode can also be used in its application as dynamic voltage restorer. Detailed analysis of the proposed converter is given, and experimental results are also provided.

Wysokoczęstotliwościowe, dyskretne drajwery małej mocy dedykowane do tranzystorów MOSFET serii DE

This paper presents a systematic approach to design high performance discrete gate driver circuits for high speed switching applications. In the project tested three integrated drivers IXYS Corporation and additionally eight discrete drivers have been designed. Additionally, in this paper presents characteristic power input by the drivers (fig.4) for three operating states: at idle, at capacitance load 3 nF and at gate MOSFET 501N16A load. Also in this paper presents voltage waveforms (fig.5) and pictures of the thermal camera. At the end presents the measurements of parasitic parameters (inductances LDR, capacities COUT and resistances RDR) for all drivers. (The Low-Losses and Fast Switching Hybrid Drivers for DE Series MOSFET Transistors).

Reducing Switching Losses in BLDC Motor Drives by Reducing Body Diode Conduction of MOSFETs

This paper presents a new power electronic topology that aims to reduce switching losses in hard-switched inverters for brushless dc (BLDC) motor drives. This is achieved by extending the benefits of synchronous rectification used in low-voltage switch-mode dc-dc conversion to high-voltage motor drive applications and by minimizing the reverse conduction behavior of the intrinsic body diode of the synchronous rectifier MOSFET. The proposed topology for reducing body diode conduction includes the addition of a MOSFET in series with the rectifying switch and a SiC Schottky diode around the series switch combination. This paper focuses on theory, simulations, and experimental results and validates the benefits of proposed new topology for BLDC motor drive applications. An extension of this topology for sinusoidal back electromotive force permanent-magnet motors is also presented.

Reliability Analysis and Performance Degradation of a Boost Converter

In general, power converters are operated in closed-loop systems, and any characteristic variations in one component will simultaneously alter the operating point of other components, resulting in a shift in overall reliability profile. This interdependence makes the reliability of a converter a complex function of time and operating conditions; therefore, the application may demand periodic replacement of converters to avoid downtime and maintenance cost. By knowing the present state of health and the remaining life of a power converter, it is possible to reduce the maintenance cost for expensive high-power converters. This paper presents a reliability analysis for a boost converter, although this method could be used to any power converter being operated using closed-loop controls. Through the conducted study, it is revealed that the reliability of a boost converter having control loops degrades with time, and this paper presents a method to calculate time-varying reliability of a boost converter as a function of characteristic variations in different components in the circuit. In addition, the effects of operating and ambient conditions have been included in the reliability model as well. It was found that any increase in the ON-state resistance of the MOSFET or equivalent series resistance of the output capacitor decreases the overall reliability of the converter. However, any variation in the capacitance has a more complex impact on the converter's reliability. This paper is a step forward to the power-converter reliability analysis because the cumulative effect of multiple degraded components has been considered in the reliability model.

SPICE Modeling of Double-Gate Tunnel-FETs Including Channel Transports

SPICE modeling of double-gate (DG) tunnel FETs (TFETs) including channel transports is reported. An ideal drain current model neglecting the channel transport is developed first. It captures the interband tunneling characteristics, describes their geometry dependences, and is suitable for DG TFETs with limited drivability. The ideal current model and previously proposed charge model are then extended to include the channel transports. One way to model the transport is appending a DG MOSFET in series with the ideal TFET model. The dependences of TFETs current and terminal charges on channel transports are reproduced. Another way by inserting a resistance at the TFET source side is also proposed with reduced simulation time.

Development of a pulsed power system using MOSFETs and underwater pulsed electric discharge

We have developed a high-frequency pulsed power generation system using either ten or twenty MOSFETs in series. The operation principle of the circuit was elucidated, and the experimental results confirmed the operation of the developed circuit. When twenty MOSFETs were used, repetitive operation was achieved at an output voltage of 10 kV and a frequency of 1 kHz. A preliminary experiment on underwater pulsed electrical discharge is performed, and the occurrence of underwater pulsed electric discharge was confirmed.