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Showing papers on "Breakdown voltage published in 1978"


Journal ArticleDOI
TL;DR: In this article, an accurate numerical model of avalanche breakdown in MOSFETs is presented, which uses an accurate electric field distribution calculated by a two-dimensional numerical analysis, and introduces multiplication factors for a high-field path and the channel current path.
Abstract: An accurate numerical model of avalanche breakdown in MOSFET's is presented. Features of this model are a) use of an accurate electric-field distribution calculated by a two-dimensional numerical analysis, b) introduction of multiplication factors for a high-field path and the channel current path, and c) incorporation of the feedback effect of the excess substrate current induced by impact ionization into the two-dimensional calculation. This model is applied to normal breakdown observed in p-MOSFET's and to negative-resistance breakdown (snap-back or switchback breakdown) observed in short-channel n-MOSFET's. Excess substrate current generated from channel current by impact ionization causes a significant voltage drop across the substrate resistance in short-channel n-MOSFET's. This voltage forward-biases the source-substrate junction and increases channel current causing a positive feedback effect. This results in a decrease of the breakdown voltage and leads to negative-resistance characteristics. Current-voltage characteristics calculated by the present model agree very well with experimental results. Another model, highly simplified and convenient for device design, is also presented. It predicts some advantages of p-MOSFET's over n-MOSFET's from the standpoint of avalanche breakdown voltage, particularly in the submicrometer channel-length range.

160 citations


Proceedings ArticleDOI
01 Jan 1978
TL;DR: In this paper, a new breakdown mechanism in a short channel MOS transistor is proposed based on experimental measurements of substrate currents, which is similar to the operation of a unijunction transistor during switching.
Abstract: In this paper a new breakdown mechanism in a short channel MOS transistor is proposed based on experimental measurements of substrate currents. We have observed a negative resistance in the substrate current followed by conductivity modulation, similar to the operation of a unijunction transistor during switching. By adding an external substrate resistance, saturation of the substrate current was observed in conjunction with the turn-on of the parasitic NPN (source-substrate-drain) bi-polar transistor. Breakdown of the device will occur when the drain bias reaches BV CEO of this parasitic bipolar transistor. The channel length dependence of the breakdown voltage of the short channel MOS transistor can then be explained by the dependence of BV CEO on the base width.

74 citations


Proceedings ArticleDOI
K. Nishiuchi1, H. Oka, T. Nakamura, H. Ishikawa, M. Shinoda 
01 Jan 1978
TL;DR: In this paper, the performance of a buried channel MOSFET with the bulk region as the conducting channel in contrast with the surface channel of the conventional device has been investigated.
Abstract: This paper presents the performance of a buried channel MOSFET (BC-MOSFET) that uses the bulk region as the conducting channel in contrast with the surface channel of the conventional device. Normally-off characteristic has been realized with the p-type silicon gate and the ion-implanted n-channel layer. Fabricated short channel BC-MOSFETs with the gate lengths of 1-3 µ have shown a small shift of threshold voltage with changing the gate length or drain bias. These devices also have high carrier mobility of 750 cm2/v.s and high breakdown voltage compared with those of the conventional device. Minimum delay time of 180 ps was obtained with a 13 stage ring oscillator which was constructed with 1 µ BC-MOSFET.

70 citations


Journal ArticleDOI
M.S. Shur1
TL;DR: In this paper, a simple analytical model of GaAs MESFET's is proposed, which is based on the assumption that the current saturation is related to the stationary Gunn domain formation at the drain side of the gate rather than to a pinchoff of the conducting channel under the gate.
Abstract: A simple analytical model of GaAs MESFET's is proposed. The model is based on the assumption that the current saturation in GaAs MESFET's is related to the stationary Gunn domain formation at the drain side of the gate rather than to a pinchoff of the conducting channel under the gate. The saturation current, channel conductance, transconductance, charge under the gate, gate-to-source and drain-togate capacitances, cutoff frequency, characteristic switching time, power-delay product, and breakdown voltage are calculated in the frame of this model. The results are verified by two-dimensional computer calculations. They agree well with the results of the computer analysis and experimental data for a 1-µm gate GaAs MESFET. It is shown that a stray gate-to-drain and gate-to-source capacitance sets up a limitation of a gate length which must be larger than or about 0.1 µm for a GaAs MESFET.

70 citations


Journal ArticleDOI
T. Furutsuka1, T. Tsuji, F. Hasegawa
TL;DR: In this paper, a simple recess structure without surface n+contact layer was investigated and it was found that the drain breakdown voltage was improved by increasing the thickness of the active epitaxial layer, due to relaxation of the field at the drain region.
Abstract: Dependence of the drain-to-source breakdown voltage on the drain structure of GaAs power FET's was investigated. It was found that the drain breakdown voltage is improved by a simple recess structure without surface n+contact layer. This is due to relaxation of the field at the drain region by increase of the thickness of the active epitaxial layer. The GaAs MESFET with this simple recess structure could be operated up to 24 V. There was no explicit difference in the microwave properties of both recess structure devices with and without the n+contact layer. As a practical device, an output power of more than 3 W with 4-dB gain is obtained at 6.5 GHz from this simple recess and cross-over structure GaAs FET.

66 citations


Journal ArticleDOI
TL;DR: In this article, the breakdown voltage of an air gap submitted to switching surges may be determined by using a mathematical model of leader propagation, which is applied to point plane gaps, for which a number of experimental results are available.
Abstract: The breakdown voltage of an air gap submitted to switching surges may be predetermined by use of a mathematical model of leader propagation. This model is applied, in this article, to point plane gaps, for which a number of experimental results are available. It is possible to similate the development of a flashover: current, speed, visual appearence. U50 voltage and standard deviation may be deduced by simulation of test sequences and, as a result, the variations of these parameters, when the length of the gap and the shape of the applied wave vary, may be studied. Generally, results are found to be in accordance with experiments.

55 citations


Journal ArticleDOI
TL;DR: In this article, the well known breakdown theories, Townsend's generation mechanism and the streamer mechanism, are reviewed and applied to the results of breakdown in the strongly electronegative gas, sulphur-hexafluoride.
Abstract: The well known breakdown theories, Townsend's generation mechanism and the streamer mechanism, are reviewed and applied to the results of breakdown in the strongly electronegative gas, sulphur-hexafluoride. Experimental results reported in the literature on the breakdown behavior of sulphur-hexafluoride are examined in the light of these theories. The breakdown theories are used for the estimation of the breakdown voltages in pure SF6. Other factors that may affect the breakdown characteristics of SF6 have been discussed. Further areas of work have been proposed in order to obtain a better understanding of the breakdown mechanism.

51 citations


Journal ArticleDOI
TL;DR: In this paper, the authors proposed a vertical three-terminal device design with short, wide channels; a wide, lightly doped drain region; and field terminator rings at the device perimeter.
Abstract: Analysis of fundamental MOSFET parameters predicts device limits in high-voltage high-speed operation that exceed the performance of bipolar devices. The optimization of voltage, speed, and "on" resistance parameters for power MOSFET's suggests a vertical three-terminal device design with short, wide channels; a wide, lightly doped drain region; and field terminator rings at the device perimeter. Utilizing this design philosophy, VMOS transistors have been produced with source-drain breakdown voltage greater than 450 V, and 5.5-Ω "on" resistance for 2.0-mm2active area. With a high channel width packing density design and 2.5-mm2active area, a 30-V transistor has also been produced having only 0.060-Ω "on" resistance. The breakdown voltage and "on" resistance of these devices exceed the performance of other power MOSFET's currently available. Also, the switching speed of these devices (better than 15 ns) far exceeds the performance of high-voltage bipolar transistors. Measurements of drain leakage current at 200-V drain potential show a resistance ratio R_{off}/R_{on} of approximately 1010for a 20-V variation in gate-to-source voltage.

47 citations


Journal ArticleDOI
G. A. Farrall1
TL;DR: In this paper, the authors discuss the various processes that tend to limit the voltage withstanding capability of the vacuum gap during the decay of arc residue during the discharge of a power arc.
Abstract: Typically a vacuum interruptor will be used in series with a powerline which is supplying power from an AC source. In the event of a fault on that system, relaying devices provide signals to the trip mechanism of the interruptor to cause the contacts to separate, an event that ultimately causes the circuit current to be interrupted. A fault on such a system can occur at any time. The parting of the interruptor contacts is, therefore, random with respect to any given point within the alternating current half-cycle. The actual interruption of circuit current, however, always occurs near a sinusoidal zero of current. As the arc current in a vacuum interrupting device approaches a sinusoidal zero the arc cathode spots, which provide the emission to sustain the arc, becomes unstable and abruptly extinguish. The current rapidly drops to zero. Although the emission processes have ceased to function at this time, there remains within the gap volume a residue of ions, electrons, vapors and particles which require a finite length of time to disperse. Until this residue is dissipated, the ability of the electrodes and gap to withstand high voltage is diminished. The effect is especially important in circuit interrupting devices where rapidly rising voltage transients may immediately appear across the gap after current interruption. If the gap withstands these transients and the ensuing open circuit voltage, the interruption function will have been complete. If, on the other hand, these voltages produce breakdown, a power arc may be restarted. The interrupting device will then have failed to fulfill its function. The study of the processes by which a gap recovers its electric strength after arcing, therefore, helps to answer important practical questions. This paper is devoted to discussions of the various processes that tend to limit the voltage withstanding capability of the vacuum gap during the decay of arc residue. Our comments will deal principally with recovery under somewhat special low current conditions. One might question the realism of applying low current studies to phenomena which are of particular interest at the high currents appropriate to power circuit interruption. At such high currents, however, there are numerous physical processes acting simultaneously. Therefore, failure to interrupt may occur for a variety of reasons and the true cause often goes undetected. Low current experiments, on the other hand, can be designed to investigate certain specific processes which are known to occur at higher levels without introducing a number of concurrent effects which can cloud the interpretation of the result. Such studies also help to reveal fundamental information about the discharge. The following discussions fall roughly into three parts. In the first, we consider a few selected recovery strength measurements to illustrate the parameters which are likely to be generally important. These data are then used as a basis for further discussion in the second and third parts where we explore in greater detail the influence of neutral vapor and of residual ionization during recovery. Our objective in these sections is to indicate the processes and material properties that are significant to the recovery of dielectric strength in vacuum.

45 citations


Journal ArticleDOI
TL;DR: In this article, the breakdown characteristics of gas insulated systems were investigated for DC and switching impulse voltage superposed upon DC of opposite polarity in laboratory-clean conditions, and the results showed that the breakdown voltage of a SF6 gas gap for DC voltage is approximately 80 percent of that for AC crest value at pressure of 3.5kg/cm2 abs.
Abstract: The breakdown characteristics of gas insulated systems were investigated for DC and switching impulse voltage superposed upon DC of opposite polarity in laboratory-clean conditions. The breakdown voltage of a SF6 gas gap for DC voltage is approximately 80 percent of that for AC crest value at pressure of 3.5kg/cm2 abs., while an epoxy cast gap withstands the DC voltage by 1.7 times of the AC crest value. However, when the short epoxy cast gap is subjected to the combined voltage of DC and switching impulse of reverse polarity, the switching impulse breakdown voltage is strongly affected by the preset level of DC voltage. On the other hand, the superposed switching impulse breakdown voltages of conical insulators, for supporting a high voltage conductor in a cylindrical enclosure, are only slightly influenced by the DC voltage of reverse polarity. Therefore the combination of SFb gas and epoxy resin may be used effectively as an insulation system of the HVDC gas insulated substation.

37 citations


Patent
David James Coe1
15 Dec 1978
TL;DR: In this article, an insulated-gate field-effect transistor has polycrystalline silicon or other resistance layer connected between its gate and drain electrode to permit during operation of the device the formation of a potential distribution along the resistance layer.
Abstract: A field-effect device, e.g. an insulated-gate field-effect transistor has field-relief means in the form of a polycrystalline silicon or other resistance layer connected between its gate and drain electrode to permit during operation of the device the formation of a potential distribution (V G , V D ) along the resistance layer. The resistance layer and its potential distribution extend over the current path in a low-doped drain zone to permit a high drain breakdown voltage without an unacceptable increase in drain series resistance or unacceptable decrease in transconductance.

Journal ArticleDOI
Richard M. Cohen1, Robert J. Huber1, Jiří Janata1, R.W. Ure1, S.D. Moss1 
TL;DR: This paper showed that Si 3 N 4 is a satisfactory insulator on silicon whereas thermally grown SiO 2 is not The results can be explained in terms of micro-crack formation in SiO2, and the breakdown voltage was found to be relatively independent of the siO 2 thickness and crack sizes were estimated to be of the order of a few tens of angstroms.

Journal ArticleDOI
K. Natori1, I. Sasaki, F. Masuoka
TL;DR: In this article, the concave MOSFET was analyzed by the two-dimensional numerical method and the theoretical result is in reasonable agreement with the experimental result, and it is observed that the threshold voltage depends strongly on the substrate bias voltage as compared with the long-channel normal MOS FET.
Abstract: The electrical characteristics of the concave MOSFET are analyzed by the two-dimensional numerical method and the theoretical result is in reasonable agreement with the experimental result. Even if the channel length of the concave MOSFET is short, the obtained current-voltage characteristics of the concave MOSFET are quite similar to those of the long-channel normal MOSFET and can be approximated by the normal MOSFET formula. In short-channel concave MOSFET's, the threshold voltage lowering due to the short-channel effect is not observed. It is observed that the threshold voltage of the concave MOSFET depends strongly on the substrate bias voltage as compared with the long-channel normal MOSFET. These observed results are followed by the two-dimensional numerical analysis. The increase of the punch-through breakdown voltage as well as that of the surface induced avalanche breakdown voltage of the concave MOSFET is predicted theoretically. The equivalent circuit model of the concave MOSFET is shown and discussed.

Journal ArticleDOI
TL;DR: In this paper, the peak bulk and surface electric fields at breakdown were predicted for all positive and double positive beveled devices with and without a field ring and negative bevel.
Abstract: Techniques previously presented for predicting breakdown voltage on planar devices with and without a field ring and in negative beveled devices are greatly extended so that the peak bulk and surface electric fields at breakdown can now be predicted. In addition, new techniques are described which for the first time allow the peak bulk and surface electric fields to be predicted for all positive and double positive beveled devices. Using this paper it becomes possible to predict peak bulk and surface electric fields as well as breakdown voltage for all planar and beveled devices. This is accomplished by the use or normalization procedures which allow dependencies on the substrate doping, junction depth, surface concentration, junction curvature, and bevel angle to be reduced to a single dependence. It is shown that the positive bevel is most effective in reducing surface electric fields with the negative bevel, double positive bevel, and the field ring for planar devices in decreasing order of effectiveness.

Patent
30 May 1978
TL;DR: In this paper, a V-shaped recess at the intersection of each bit line and word line that extends across the diffused bit line, (which serves as the transistor drain) and into the substrate is isolated below and above the crossing bit and word lines by thin oxide layers.
Abstract: A semiconductor electrically programmable read only memory device (EPROM) utilizes an array of memory cells each in the form of a single V-type MOSFET which achieves the normal AND function (Data-Word Address) using a capacitance coupled version of threshold logic. Each MOSFET is formed by a V-shaped recess at the intersection of each bit line and word line that extends across the diffused bit line, (which serves as the transistor drain) and into the substrate (which serves as the source and ground plane of the device). A similarly V-shaped floating gate is isolated below and above the crossing bit and word lines by thin oxide layers. A ring of P-type conductive material around the upper end of each V-shaped recess and adjacent its surrounding N-type drain region serves to lower the required programming voltage without increasing the device threshold voltage.

Journal ArticleDOI
TL;DR: In this paper, breakdown voltages for abrupt pn junctions in the nine III-V semiconductors of AlP, AlAs, AlSb, GaP, GaAs, GaSb and InSb were calculated.
Abstract: Breakdown voltages have been calculated for abrupt p‐n junctions in the nine III‐V semiconductors of AlP, AlAs, AlSb, GaP, GaAs, GaSb, InP, InAs, and InSb. Parameters needed in the breakdown voltage calculations such as the mean free path for scattering and the average phonon loss have been evaluated using a Monte Carlo transport calculation at electric field values characteristic of breakdown.

Proceedings ArticleDOI
01 Jan 1978
TL;DR: In this paper, the reverse bias second breakdown susceptibility of high-voltage, fast-switching power transistors has been investigated and a unique test circuit is described which permits devices to be taken into reverse-bias second breakdown many times with little or no apparent degradation.
Abstract: Some experimental observations of the switching characteristics and second breakdown susceptibility of high-voltage, fast-switching power transistors are discussed. A unique test circuit is described which permits devices to be taken into reverse-bias second breakdown many times with little or no apparent degradation. Evidence for the constriction of emitter current to the centers of the emitter fingers during the time associated with the extraction of stored charge is presented, three modes of reverse-bias second breakdown are shown, and reverse-bias safe-operating-area limits which have been nondestructively determined are shown.

Journal ArticleDOI
TL;DR: In this paper, the dielectric strength of superconductivity and low resistivity at cryogenic temperatures is investigated and whether Paschen's law is valid over a wide range of low temperatures or not.

Proceedings ArticleDOI
12 Jun 1978
TL;DR: For both DC and AC, the ratio of breakdown voltage for clean oil to oil with non-conducting particles is nearly the same as mentioned in this paper, and for conducting particles the ratio for DC is generally larger than for AC.
Abstract: Particles influence both AC and DC voltage breakdown in insulating oil. Larger and conducting particles decrease the breakdown voltage most. For both DC and AC the ratio of breakdown voltage for clean oil to oil with non-conducting particles is nearly the same. For conducting particles the ratio for DC is generally larger than for AC. Particle concentration and motion is influenced by DC and AC stress in different ways. Particles may be drawn into or expelled from high stress regions. Fine particles may agglomerate or be dispersed. Particle chains may develop. These complex physical factors have not been related directly to voltage breakdown in the oil. Particles may cause partial discharges to develop in oil but these discharges also have not been related directly to short time breakdown of the oil.

Journal ArticleDOI
TL;DR: In this paper, failure in ceramic capacitors due to high-impulse voltages was investigated to determine the parameters which limit the breakdown voltage, and it was found that the breakdown field strength is a function of the dielectric constant, the Dielectric thickness, and the capacitor area.
Abstract: Failure in ceramic capacitors due to high-impulse voltages was investigated to determine the parameters which limit the breakdown voltage. It was found that the breakdown field strength is a function of the dielectric constant, the dielectric thickness, and the capacitor area. There was little correlation between the breakdown voltage and the rated voltage. Breakdown usually occurred at the edge of the electrodes, and only small changes in capacitance and dissipation factor resulted.

Journal ArticleDOI
TL;DR: In this paper, a theory has been developed to explain hot electron injection and trapping in the oxide and its effect on the breakdown voltage, and a comparison of results predicted by theory, with the experiments has also been carried out.
Abstract: Junction breakdown walkout in p-n junctions has been investigated in this paper. It has been shown that walkout is closely related to the avalanching in the junction. During the time the junction is subjected to the reverse breakdown, because of avalanching, hot electrons are generated in the depletion region. Some of the hot electrons have enough energy to cross the oxide-silicon barrier and to go into the conduction band of the oxide. The electrons are trapped in the traps and charge the oxide negatively, resulting in reduction of electric field intensity in the surface depletion region of the p-n junction. This results in an increase of the breakdown voltage. A theory has been developed to explain hot electron injection and trapping in the oxide and its effect on the breakdown voltage. A comparison of results predicted by theory, with the experiments has also been carried out.

Proceedings ArticleDOI
D.L. Crook1
01 Jan 1978
TL;DR: In this paper, the authors discuss techniques of evaluating long-term oxide reliability at the wafer level using statistical analysis of the electric field distribution of MOS capacitor primary breakdown and monitoring time dependent breakdowns of test capacitors during a short four second voltage accelerated stress test.
Abstract: This paper discusses techniques of evaluating long term oxide reliability at the wafer level. These techniques are presently used in the development of high reliability oxide processes. The first technique involves a statistical analysis of the electric field distribution of MOS capacitor primary breakdown. The second technique consists of monitoring time dependent breakdowns of test capacitors during a short four second voltage accelerated stress test. Using an empirically derived voltage acceleration factor (107/MV/cm) failure rates at nominal voltages can be accurately extrapolated from these voltage accelerated data. A discussion of how these techniques can be used to determine oxide reliability is presented.

Journal ArticleDOI
TL;DR: In this paper, it has been shown that the ac or dc voltage breakdown can be described by the following equation: U=G x dO x t where 6 is the gas density, d the gap length and G, o, t are constants.
Abstract: This paper presents a direct method for computing the uniform field breakdown of gases. It has been found that the ac or dc voltage breakdown can be described by the following equation: U=G x dO x t Where 6 is the gas density, d the gap length and G, o, t are constants. The equation has been verified for many usual gases (air, N2, CO2, SF6...) andfor a wide range of pressures and voitageg. The data obtained show a good agreement with the results of many authors including I.E.C. Standard 52.

Patent
13 Jun 1978
TL;DR: In this paper, a MISFET of small on-resistance and high breakdown voltage is produced by disposing an N type layer in adjacent to the N type drain layer of an n type Si substrate and providing the electrode of the same potential as that of the source through an insulation film on the n type layer.
Abstract: PURPOSE:To produce a MISFET of small on-resistance and high breakdown voltage by disposing an N type layer in adjacent to the N type drain layer of an N type Si substrate and providing the electrode of the same potential as that of the source through an insulation film on the N type layer.

Journal ArticleDOI
TL;DR: In this paper, the tradeoff between threshold voltage and the punchthrough voltage of the channel diffusion was discussed for junction isolated DMOS transistors suitable for monolithic integration. But the tradeoffs were not only focused on threshold voltage, but also on the avalanche breakdown voltage, on-resistance, and source-to-substrate punch-through voltage.
Abstract: The design of junction isolated DMOS transistors suitable for monolithic integration has been studied. The purpose of this correspondence is to describe one of the key tradeoffs when designing these devices for high breakdown voltages (200 V for our example). It is a tradeoff primarily between threshold voltage and the punchthrough voltage of the channel diffusion, however, the avalanche breakdown voltage, on-resistance, and source-to-substrate punchthrough voltage are also affected. As an example, the design of a device for 200-V operation is described. The discussion is, however, general and can be applied to other DMOS designs as well.

Journal ArticleDOI
TL;DR: In this article, the ac corona onset and breakdown voltages have been measured for rod-plane and rod-rod gaps in hydrogen, SF6, and hydrogen-SF6 mixtures for pressures between 1 and 5 bar, with gaps up to 14 cm, and voltages up to 250 kV rms.
Abstract: The ac corona onset and breakdown voltages have been measured for rod-plane and rod-rod gaps in hydrogen, SF6, and hydrogen-SF6 mixtures for pressures between 1 and 5 bar, with gaps up to 14 cm, and voltages up to 250 kV rms. The addition to hydrogen of quantities of SF6 as low as 0.002% by volume resulted in a substantial increase in breakdown voltage of typically 70%. The corona onset voltage of the hydrogen was only increased by large additions of SF6 above 1%. With the mixtures for rod-rod gaps, breakdown values were obtained up to 70% higher than for SF6 alone, and there was no maximum in the breakdown voltage-pressure characteristic in contrast to the case for SF6. Very intense, stable glow currents of up to 20 mA were recorded. The characteristics and mechanisms of the various corona modes are discussed.

Journal ArticleDOI
TL;DR: In this article, the surface voltage at insulator edges can be approximated by an exponential expression based on an electron current density balance, which results in a discharge voltage gradient down the insulator edge to ground of about 1.5×105 V/cm.
Abstract: Insulating surfaces on geosynchronous satellites have been charged by geomagnetic substorms to a point where discharges occur. The electromagnetic pulses from these discharges couple into satellite electronic systems disrupting operations. Laboratory tests conducted on insulator charging have indicated that discharges appear to be initiated at insulator edges where voltage gradients can exist. An experimental investigation has been conducted to measure edge voltage gradients on silvered Teflon samples as they are charged by monoenergetic electron beams. It has been found that the surface voltage at insulator edges can be approximated by an exponential expression based on an electron current density balance. Using this expression at known breakdown conditions results in a discharge voltage gradient down the insulator edge to ground of about 1.5×105 V/cm. Seams between insulation strips and imperfections in insulation can intensify voltage gradients and contribute to discharges. It appears that such discharges can occur on satellite surfaces in space.

Patent
09 Mar 1978
TL;DR: In this paper, a high voltage capacitor is charged, and discharged across a spark gap and ignition electrodes when a threshold value voltage has been attained, which is higher than the breakdown voltage at the ignition electrodes.
Abstract: In the igniting process a high voltage capacitor is charged, and discharged across a spark gap and ignition electrodes when a threshold value voltage has been attained. This voltage is higher than the breakdown voltage at the ignition electrodes. The energy transfer takes place in the starting phase of the ignition spark, i.e. possibly in the breakdown phase of the ignition start. In an appropriate spark plug the presparking path is as near as possible to the ignition electrodes. It has the lowest possible ohmic and inductive resistance, and its threshold value voltage is externally controllable. Between the capacitor and the ignition electrodes the inductance and ohmic resistance of the supply line to the electrodes is as low as possible, at least at frequencies exceeding 50 MHz.

Patent
Britton John1
15 Jun 1978
TL;DR: In this paper, an electric discharge lamp circuit is presented where rapid starting is obtained by charging a ballast impedance capacitance via a unidirectional current conducting path in a sense such as to breakdown a voltage breakdown device in the control electrode lead of a controllable switching device connected with the lamp.
Abstract: An electric discharge lamp circuit arrangement wherein rapid starting of the lamp is obtained by charging a ballast impedance capacitance via a unidirectional current conducting path in a sense such as to breakdown a voltage breakdown device in the control electrode lead of a controllable switching device connected with the lamp to provide a current path between the supply terminals comprising, in series, the capacitance, heating means for the lamp main electrodes and the switching device. On breakdown, the switching device temporarily conducts to complete the series path and cause a pulse of current to flow through the heating means, whereafter the capacitor recharges and a further current pulse is produced. The unidirectional current path may extend through the breakdown device or by-pass the breakdown device via a rectifier.

Patent
08 Sep 1978
TL;DR: In this paper, a dual output simultaneous firing circuit with a simultaneity of 20 to 200 nanoseconds is presented, where the breakdown voltages of the fuse safety gaps have a large disparity.
Abstract: A dual output simultaneous firing circuit which provides a means for explng fuse wires with a simultaneity of 20 to 200 nanoseconds even though the breakdown voltages of the fuse safety gaps have a large disparity A DC voltage charges high voltage capacitors When the charge voltage reaches the lower breakdown voltage of one safety gap, that fuse explodes A balancing transformer induces momentarily an equal voltage which adds to the existing voltage on the undischarged capacitor The additional charge breaks down the other safety gap causing the other fuse to explode