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Showing papers on "Static induction transistor published in 1970"


Journal ArticleDOI
D. P. Kennedy1, R. R. O'Brien1
TL;DR: In this paper, a two-dimensional analysis of the mechanisms of operation for a junction field effect transistor is presented, focusing on the process of electric current saturation in both wide gate and narrow gate structures.
Abstract: A two-dimensional analysis is presented of the mechanisms of operation for a junction field-effect transistor. Particular emphasis is placed upon the process of electric current saturation in both wide gate and narrow gate structures. It is shown that velocity saturated carrier transport in a source-drain channel produces heretofore unreported mechanisms of device operation. Comparisons made between the conclusions derived from this two-dimensional analysis and the conventional one-dimensional theory of JFET operation are presented in graphic form.

110 citations


Patent
Bentchkowsky D Frohman1
15 Jun 1970
TL;DR: In this paper, a floating gate transistor comprising a floating silicon or metal gate in a field effect transistor which is particularly useful in a read-only memory is disclosed, where the gate which is surrounded by an insulative material such as SiO2 is charged by transferring charged particles across the insulation from the substrate during an avalanche (breakdown) condition in the source or drain junctions of the transistor.
Abstract: A floating gate transistor comprising a floating silicon or metal gate in a field effect transistor which is particularly useful in a read-only memory is disclosed. The gate which is surrounded by an insulative material such as SiO2 is charged by transferring charged particles (i.e., electrons) across the insulation from the substrate during an avalanche (breakdown) condition in the source or drain junctions of the transistor.

57 citations


Patent
22 Sep 1970
TL;DR: In this article, a semiconductor device includes a common substrate, on the one side of which there are provided an insulated gate field effect transistor and bipolar transistor for protecting the former transistor from the failure.
Abstract: A semiconductor device includes a common substrate, on the one side of which there are provided an insulated gate field effect transistor and bipolar transistor for protecting the former transistor from the failure. The gate of the former is electrically connected to the emitter of the latter to have the same potential.

30 citations


Patent
22 Apr 1970
TL;DR: In this paper, the sum of threshold voltages of two transistors of different conductivity type is employed as a reference level in voltage sensing and other circuits, where a first transistor connected as a diode and its current source are connected in series between a pair of terminals to which a voltage to be sensed is applied.
Abstract: The sum of the threshold voltages of two transistors of different conductivity type is employed as a reference level in voltage sensing and other circuits A first transistor connected as a diode and its current source are connected in series between a pair of terminals to which a voltage to be sensed is applied A second transistor of different conductivity type than the first transistor is connected at its control electrode to the connection of the diode to its current source The conduction path of the second transistor in series with its load is connected at at least one end to one of the pair of terminals

27 citations


Patent
03 Apr 1970
TL;DR: In this paper, a switching regulator employs between a primary power source and a switching transistor a sensing circuit which senses the current being drawn through the switching transistor by a load and a storage filter circuit having a large series inductance.
Abstract: A switching regulator employs between a primary power source and a switching transistor a sensing circuit which senses the current being drawn through the switching transistor by a load. A storage filter circuit having a large series inductance is connected between the load and the switching transistor. A feedback network is connected between the output connection of the storage filter circuit and the switching transistor to activate the switching transistor when the output voltage falls below a predetermined value and to inactivate the switching transistor when the output voltage exceeds a predetermined reference value. The sensing means which senses gradual overloads and a timing circuit which senses abrupt overloads are coupled to the switching transistor via a threshold circuit which compares the output signals from the sensing means and the timing circuits to a predetermined threshold level. When either of the output signals exceeds the threshold level, the switching transistor is opened interrupting the current from the primary power source.

25 citations


Patent
09 Apr 1970
TL;DR: In this article, the loss of phase detector employs a plurality of rectifiers each of which is connected between a transistor and a corresponding phase of a polyphase AC power system, each rectifier couples a signal to the transistor when the corresponding phase provides output power.
Abstract: The loss of phase detector employs a plurality of rectifiers each of which is connected between a transistor and a corresponding phase of a polyphase AC power system. Each rectifier couples a signal to the transistor when the corresponding phase provides output power. These signals render the transistor nonconductive. When power is lost in any of the phases of the polyphase system or when voltage in the system decreases below a predetermined value, the transistor is rendered conductive so that a capacitor in series with the transistor is charged by a reference voltage which is connected to the transistor. The charge on this capacitor provides a signal that activates an indicating device which warns that power has been lost in one of the phases of the polyphase power system.

21 citations


Patent
27 Apr 1970
TL;DR: In this article, a control circuit for supplying pulses of current from a voltage source through a load which may vary in its effective impedance and wherein a power transistor is in series with the load to turn the current on and off.
Abstract: A control circuit for supplying pulses of current, with a variable duty cycle, from a voltage source through a load which may vary in its effective impedance and wherein a power transistor is in series with the load to turn the current on and off. The transistor is driven always to collector current saturation when it is turned on so that power loss in the transistor and excessive heating are substantially minimized. But when the effective load impedance is high, the base-emitter current required to saturate the transistor is considerably less than that required when the effective load impedance is low. To avoid energy dissipation and loss due to unnecessarily high emitter-base current, the base-emitter circuit includes a control transistor which acts as a controllable impedance, the control transistor receiving emitter-base current proportional to the voltage drop across the power transistor so that emitter-base current of the power transistor is always just sufficiently great to keep the power transistor saturated. The average current through the load, e.g., a DC motor, is varied by employing a multivibrator adjustable in its duty cycle to produce a control signal which alternately enables or disables the control transistor. And to avoid energy loss due to slow turnoff of the power transistor, the emitter-base junction of the power transistor is shunted by a transistor automatically switched to its conductive, low-impedance state or its nonconductive, highimpedance state by a signal from the multivibrator when the power transistor is turned on or off. These energy-conserving features are of particular benefit in applications such as speed control of a DC motor in golf carts, fork lift trucks and the like where the voltage source is a battery and maximum usage between recharges is important.

16 citations


Journal ArticleDOI
TL;DR: In this article, the nonuniform emitter current distribution effect on power transistor thermal stability is discussed, and the temperature distribution effects are discussed as a function of the current distribution.
Abstract: Nonuniform emitter current distribution effect on power transistor thermal stability, discussing temperature distribution effects

15 citations


Patent
26 Oct 1970
TL;DR: A circuit for clamping a voltage induced across an inductor utilizing a Zener diode to control the energy dissipation of the inductor through a transistor is described in this article, where the voltage generated by the induction is prevented from applying too high a voltage across the collector-emitter circuit of the output transistor, which might damage the transistor.
Abstract: A circuit for clamping a voltage induced across an inductor utilizes a Zener diode to control the energy dissipation of the inductor through a transistor. A driver circuit for an inductor includes a Zener diode and an opposing diode connected across the series combination of the base-emitter junction of an emitter-follower output transistor and the inductor driven thereby. When the transistor is conducting, the inductor is energized and no current flows through the Zener diode. When the transistor is caused to cease conduction, the field of the coil of the electromagnet collapses, generating a voltage that is applied to the emitter of the output transistor. If the voltage thus generated is greater than the Zener breakdown voltage, the Zener diode breaks down and provides a bias current to the base of the output transistor to permit further conduction of the transistor and clamps the voltage at the emitter of the transistor to substantially the value of the Zener breakdown voltage. The voltage generated by the inductor is thus prevented from applying too high a voltage across the collector-emitter circuit of the output transistor, which might damage the transistor. The transistor continues to conduct during the dissipation of the energy stored in the inductor until the inductor is almost fully deenergized and can no longer generate a voltage equal to the Zener diode breakdown voltage. The output transistor is then rendered nonconductive, completing the deenergization of the inductor.

14 citations


Patent
10 Aug 1970
TL;DR: In this paper, a controllable shunt current path for a first transistor, which is connected in shunt with the emitter-to-base path of a conducting output transistor, is described.
Abstract: A controllable shunt current path such as the conducting emitter-to-collector path of a first transistor, is connected in shunt with the emitter-to-base path of a conducting output transistor. In response to a turnoff signal for the output transistor, the first transistor is caused to conduct more heavily in a direction to stop forward conduction of the emitterto-base diode of the output transistor and in this way to speed up its turnoff. Other features of the circuits illustrated include overload current protection and means for speeding up the discharge of any charge present at an output terminal upon switching of an output transistor from a nonconducting to a conducting condition. One of the circuits illustrated also includes means for ensuring proper sharing of current drive to a pair of transistors and means for ensuring ''''soft'''' saturation of the output transistor.

12 citations


Patent
30 Jan 1970
TL;DR: In this article, a body of semiconductor material consisting of a controlled rectifier switch and a transistor each sharing a common anode is defined as a '''''THYTRAN'' device.
Abstract: A body of semiconductor material comprises a controlled rectifier switch and a transistor each sharing a common anode. The controlled rectifier provides the base drive which is necessary to keep the transistor in an ''''on'''' condition. Once operating, the transistor functionally does not see the controlled rectifier in the electrical circuit. When it is desired to shut off the transistor, the necessary signal is sent to the gate region of the controlled rectifier and the rectifier is turned off thereby removing the base drive from the base region of the transistor which in turn turns all of the regions of the transistor off substantially simultaneously. This type of device is designated by the term ''''THYTRAN.

Patent
28 May 1970
TL;DR: In this paper, a Darlington circuit is described where the primary of a step-up transformer is connected with diodes to charge a capacitor and a holding transistor connects the base of one charging transistor to the battery, and a bypass transistor in parallel with the one resistor permits turnoff of the holding transistor.
Abstract: A pair of main charging transistors are connected in a Darlington circuit in series with the primary of a step-up transformer having a saturable nonlinear core to a battery. The secondary of the transformer is connected in series with diodes to charge a capacitor. A holding transistor connects the base of one charging transistor to the battery. A pair of resistors are connected in series with each other and in series with the main charging transistors. The junction of the resistors is connected to the base of the holding transistor. A bypass transistor in parallel with the one resistor permits turnoff of the holding transistor. A current-sensing resistor is connected across the input elements of the bypass transistor and in series with the primary winding and the main charging transistors. A controlled rectifier or other rapid-acting and gated switch means connects the capacitor to the spark plugs of an internal combustion engine. The gate is connected to the output circuit of the holding transistor by means of a simple capacitor couple and fires to discharge the capacitor upon turn-on of the holding transistor.

Patent
10 Dec 1970
TL;DR: In this article, a low saturation resistance, very low offset voltage, monolithic analog switch is provided which has high impedance in the off state; this switch being produced by fabricating a transistor on a chip.
Abstract: A low saturation resistance, very low offset voltage, monolithic, analog switch is provided which has high impedance in the off state; this switch being produced by fabricating a transistor on a chip. The transistor is adapted to have its base collector junction forward biased and its emitter base junction reverse biased. The parasitic action of a further transistor including the base and the collector of the inversely biased transistor and the substrate on which the inversely biased transistor is deposited, is eliminated. The inverse beta of the transistor switch is increased, and also the distributed current crowding effects in the so provided transistor is minimized.

Patent
John H Gliever1
19 Mar 1970
TL;DR: In this article, a pulse transformer is added to a switching regulator power supply by placing its primary in series with the commutating diode and its secondary between the emitter and the base of the switching transistor through a bias resistor.
Abstract: A pulse transformer is added to a switching regulator power supply by placing its primary in series with the commutating diode and its secondary between the emitter and the base of the switching transistor through a bias resistor. When the switching transistor starts to turn off, a pulse from the transformer helps turn off the switching transistor faster by removing the stored charge from the base, thus reducing power dissipation in the transistor.


Patent
24 Sep 1970
TL;DR: In this paper, a transistor having base and emitter electrodes coupled in parallel with a PN-junction poled in the same direction as the base-emitter junction of the transistor is described.
Abstract: An electrical circuit includes a transistor having base and emitter electrodes coupled in parallel with a PN-junction poled in the same direction as the base-emitter junction of the transistor. A first resistor couples the collector electrode of the transistor to a direct voltage source, while second and third resistors serially couple the source to the transistor''s emitter electrode. The base electrode of the transistor is coupled to the junction of the second and third resistors, the resistance values of which are selected to provide a predetermined resistance ratio there-between. With the PN-junction then coupled across the third resistor, the resistance value of the first and second resistors are further selected substantially equal to provide a direct voltage output at the collector electrode of the transistor which is primarily dependent on the predetermined resistance ratio between the second and third resistors and independent of the value of the direct voltage source.

Patent
Gunther Schuette1
28 May 1970
TL;DR: A silicon-controlled rectifier has the anode thereof connected to the base electrode of the transistor and the cathode thereof coupled to the emitter to be in parallel with the base-emitter junction as discussed by the authors.
Abstract: An ignition system has a transistor connected in series with a primary winding of a conventional spark coil, and a sensing resistor is also connected in series with the transistor A silicon-controlled rectifier has the anode thereof connected to the base electrode of the transistor and the cathode thereof coupled to the emitter of the transistor effectively to be in parallel with the base-emitter junction The gate electrode of the silicon-controlled rectifier is coupled to the sensing resistor to be rendered conductive in response to a predetermined voltage level developed at the sensing resistor The siliconcontrolled rectifier, when conductive, decreases the current flow through the transistor and the primary winding of the spark coil and, when nonconductive, increases the current flow through the transistor and the primary winding of the spark coil

Patent
19 Jan 1970
TL;DR: A lateral transistor serving as a minority transistor in an integrated circuit has a region buried in the base region and having an opposite conduction type to the base regions as mentioned in this paper, and this region is called the lateral transistor region.
Abstract: A lateral transistor serving as a minority transistor in an integrated circuit has a region buried in the base region and having an opposite conduction type to the base region.

Patent
08 Sep 1970
TL;DR: In this paper, a programmable DC power supply including a proportionally controlled transistor connected in series with the load for varying the load current in accordance with the magnitude of a control signal applied to the transistor.
Abstract: A programmable DC power supply including a proportionally controlled transistor connected in series with the load for varying the load current in accordance with the magnitude of a control signal applied to the transistor. A detector coupled across the transistor functions to sense high and low voltage thresholds and thereupon select an incrementally higher or lower voltage for application to the load to assure that the transistor operates continuously in its proportional range, thereby enabling the input signal to maintain control of the load current.

Patent
F. Norian Roger1, H. Koning Virgil1
19 Oct 1970
TL;DR: In this article, a transition integration switching amplifier for controlling the application of a source voltage for driving an inductive load such as a four-pole, capacitor phased, hysteresis synchronous motor is presented.
Abstract: A transition integration switching amplifier for controlling the application of a source voltage for driving an inductive load such as a four-pole, capacitor phased, hysteresis synchronous motor. Symmetrical circuits are provided wherein identical signals of opposite phase control the operation of transistor switches for application of the voltage source to a center tapped motor stator. The signals would be applied to a coupling transistor, the output of which controls the input of the transistor switches. A collector to base capacitor forces a controlled transition between the saturated and cut-off states of the transistor and eliminates any high voltage transients across the transistor that may arise due to energy stored in the inductance of the motor stator.

Patent
Addis J1, Peltola R1
28 Jul 1970
TL;DR: In this article, the gain of an amplifier is controlled by the source-drain impedance of a first field-effect transistor having its gate terminal connected to the gate of a second and substantially similar field effect transistor.
Abstract: The gain of an amplifier is controlled by the source-drain impedance of a first field effect transistor having its gate terminal connected to the gate of a second and substantially similar field effect transistor. The second field effect transistor has its source-drain circuit connected in a bridge circuit also including a potentiometer with an adjustable tap providing voltage variations for unbalancing the bridge output. The bridge output operates a differential operational amplifier connected to drive the second field effect transistor for restoring bridge balance. The source-drain impedance of the second field effect transistor, and hence the source-drain impedance of the first field effect transistor, are thereby controlled in proportion to the setting of the aforementioned potentiometer, for adjusting amplifier gain.

Patent
19 Aug 1970
TL;DR: In this paper, an apparatus for controlling the temperature of a device such as an oven in which a resistance having a positive temperature coefficient of resistance is incorporated in one leg of a bridge and is used to detect the temperature to be controlled.
Abstract: An apparatus for controlling the temperature of a device such as an oven in which a resistance having a positive temperature coefficient of resistance is incorporated in one leg of a bridge and is used to detect the temperature to be controlled. The bridge is energized by an alternating voltage and any unbalance appears across output terminals which are connected respectively to the bases of a first and a second transistor also energized with the same alternating voltage. The emitters of the transistors are connected together and through a common resistance so that the initiation of current flow through one transistor will inhibit current flow through the other. Flow of current through the second transistor triggers a silicon control rectifier which in turn controls a valve which supplies fuel to a burner in the oven. The voltage supplied to the bridge leads the voltage on the control rectifier so that it is always triggered at the beginning of its conducting half cycle. A third transistor is interposed between the second transistor and the silicon control rectifier. The changes in the response of the third transistor to its ambient temperature is compensated for in one of a number of ways. One is to have an ambient temperature sensitive resistance in the leg of the bridge diagonally opposite the first leg in which the first temperature sensitive resistance is placed. A second arrangement is to insert an ambient temperature sensitive diode in a leg adjacent to the first leg. A third arrangement is to insert an ambient temperature sensitive diode across the base and emitter of the third transistor. A delay circuit is provided for charging a condensor to delay the operation of the second transistor, the charge of said condensor being permitted to build up upon the initiation of current through the first transistor.

Patent
22 Jun 1970
TL;DR: A flasher circuit has a power transistor controlling a circuit with a load therein; a multivibrator produces a timing signal applied to a second transistor for pulsing and turning on a related third control transistor which is effective in response to applying a relatively small current flow to the load to preheat the load before application of the full current as discussed by the authors.
Abstract: A flasher circuit has a power transistor controlling a circuit with a load therein; a multivibrator produces a timing signal applied to a second transistor for pulsing and turning ''''on'''' a related third control transistor which is effective in response thereto to apply a relatively small current flow to the load to preheat the load before application of the full current; additional semiconductor means, sensitive to a voltage signal or loss thereof in the load circuit due to the occurrence of a short, are effective for preventing the power transistor from being made conductive.

Patent
08 Dec 1970
TL;DR: In this paper, the maximum allowable collector power loss of a transistor is restricted to prevent the transistor from being destroyed and a second transistor is connected in circuit with the main transistor to control the power loss.
Abstract: A protective circuit for a transistor which limits the maximum allowable collector power loss so as to prevent the transistor from being destroyed is disclosed. A second transistor is connected in circuit with the main transistor to control the power loss in the main transistor. In one embodiment the protective transistor has a linear response and in another embodiment the protective circuit has a different slope in different operating ranges.

Patent
29 Jun 1970
TL;DR: In this article, a modulator circuit employing two dual-gate field effect transistors is described, where a carrier signal is applied to one gate of each transistor in a push-pull arrangement.
Abstract: A modulator circuit employing two dual gate field effect transistors. A carrier signal is applied to one gate of each transistor in a push-pull arrangement. A modulating signal is applied to the other gate of each transistor in parallel. The modulated output signal appears between the drains of the transistors.

Journal ArticleDOI
G. Roman1
TL;DR: In this article, the problem of thermal mode breakdown and current mode breakdown was considered in both the forward and reverse bias cases, and it was shown that the current-temperature system of a transistor is in a negative feedback regime as long as the temperature of the hottest part of the device does not exceed the critical value.
Abstract: Two kinds of second breakdown are considered. 1. (1) thermal mode breakdown. 2. (2) current mode breakdown. All the theoretical considerations refer to the open circuit base configuration, but the results are generalized to both the forward and reverse bias cases. The problem is approached by assuming that the transverse voltage drops are negligibly small in both the emitter and collector ohmic connections (the substrate is regarded as the ohmic connection of the collector). Calculations show that the current-temperature system of a transistor is in a negative feedback regime as long as the temperature of the hottest part of the device does not exceed the critical value. At this stage, an approximately constant current density is maintained within the ‘effective transistor’. Once the critical value is reached, the transistor goes over into a positive-feedback regime and a spontaneous constriction of the current paths results. The current mode breakdown is due to the occurrence of a negative resistance in the collector junction as a result of the Kirk effect. Once this begins in a spot, the collector capacity discharges through it and this creates a pinching-in field. The high concentration of the dissipated energy which follows brings about a final thermal breakdown.

Patent
24 Jun 1970
TL;DR: A metal insulated semiconductor (MIS) field effect transistor is operated in a gate-to-source mode as discussed by the authors, where the voltage threshold of conduction of the transistor is variable and is switched between two different stable threshold conditions in response to application of corresponding, different predetermined values of polarizing voltages applied between the gate and source terminals.
Abstract: A metal insulated semiconductor (MIS) field effect transistor is operated in a gate-to-source mode. The voltage threshold of conduction of the transistor is variable and is switched between two different stable threshold conditions in response to application of corresponding, different predetermined values of polarizing voltages applied between the gate and source terminals. Determination of the threshold condition to which the transistor is switched is effected by applying a read voltage to the gate of the transistor intermediate the voltage threshold levels and sensing the current flow between the source and drain. Since the sense voltage is less than the polarizing voltage for either condition of switching, the preset threshold condition is maintained. The transistor therefore exhibits a non-volatile memory capability. A plurality of the transistors are employed in a memory array and may be readily fabricated in integrated circuit form.

Patent
19 Feb 1970
TL;DR: In this article, an electronic switching circuit responsive to a change of resistance in a sensing element, which circuit includes an insulated gate field effect transistor, a source of power, and a resistive sensing element interconnecting the gate of the said transistor and the power source, is described.
Abstract: An electronic switching circuit responsive to a change of resistance in a sensing element, which circuit includes an insulated gate field effect transistor, a source of power, switching means interconnecting the source of power and the said transistor and a resistive sensing element interconnecting the gate of the said transistor and the power source, whereby the resistance of the sensing element controls the time required to charge the gate capacitance of the transistor and whereby the switching means opens the circuit delivering power to the transistor at such time as the gate capacitance is substantially charged.

Patent
06 Apr 1970
TL;DR: In this paper, a negative voltage is applied to the drain of a MNOS transistor to prevent the storage of a binary "1" in the dielectric of the MNOS transistors.
Abstract: A semiconductor memory array consists of an array of MNOS transistors. Each transistor possesses an hystereris relationship between the gate voltage required to turn on the transistor and a previously applied gate voltage. Thus each MNOS transistor stores, by itself, one bit of information. A binary "1" is written into a transistor by applying a voltage of a first selected magnitude to the gate of the MNOS transistor while grounding its source and drain. Applying simultaneously a negative voltage to the drain of the MNOS transistor lowers the voltage across the dielectric beneath the MNOS transistor's gate electrode and prevents the storage of a binary "1." No electrical isolation is required between the MNOS transistors.

Journal ArticleDOI
01 Jul 1970
TL;DR: In this paper, an approximate potential distribution near the drain of the junction-gate field effect transistor (JFET) is found and the excess reverse gate current is deduced based on the assumption that such current is caused by an avalanche multiplication of carriers in the channel.
Abstract: Approximate potential distribution near the drain of the junction-gate field-effect transistor (JFET) is found and is used to deduce the excess reverse gate current, based on the assumption that such current is caused by an avalanche multiplication of carriers in the channel. Theory agrees well with measurement.