Abstract: A Reverse Bipolar Junction Transistor (RBJT) integrated circuit comprises a bipolar transistor and a parallel-connected distributed diode, where the base region is connected neither to the collector electrode nor to the emitter electrode. The bipolar transistor has unusually high emitter-to-base and emitter-to-collector reverse breakdown voltages. In the case of a PNP-type RBJT, an N base region extends into a P? epitaxial layer, and a plurality of P++ collector regions extend into the base region. Each collector region is annular, and rings a corresponding diode cathode region. Parts of the epitaxial layer serve as the emitter, and other parts serve as the diode anode. Insulation features separate metal of the collector electrode from the base region, and from P? type silicon of the epitaxial layer, so that the diode cathode is separated from the base region. This separation prevents base current leakage and reduces power dissipation during steady state on operation.

Abstract: A Super Junction Field Effect Transistor (FET) device includes a charge compensation region disposed on a substrate of semiconductor material. The charge compensation region includes a set of strip-shaped P? type columns, a floating ring-shaped P? type column that surrounds the set of strip-shaped P? type columns, and a set of ring-shaped P? type columns that surrounds the floating ring-shaped P? type column. A source metal is disposed above portions of the charge compensation region. The source metal contacts each of the strip-shaped P? type columns and each of the ring-shaped P? type columns. An oxide is disposed between the floating P? type column and the source metal such that the floating P? type column is electrically isolated from the source metal. The device exhibits a breakdown voltage that is 0.2% greater than if the floating P? type column were to contact the source metal.

Abstract: An AC line filter module includes AC-to-DC rectification circuitry. The rectification circuitry includes four low forward voltage rectifiers coupled together as two high-side rectifiers and two low-side rectifiers, where each low forward voltage rectifier includes an NPN bipolar transistor and a parallel-connected diode. A current splitting pair of inductors splits a return current so that a portion of the current is supplied to the collector of an NPN bipolar transistor that is on, and so that the remainder of the current is supplied to the base of the transistor that is on. Both low-side rectifiers are driven by these current splitting inductors. A pair of base current return diodes provides base current return paths. Due to the use of NPN bipolar transistors and no PNP bipolar transistors, manufacturing cost is reduced and efficiency is improved as compared to an implementation that uses low forward voltage rectifiers having PNP transistors.

Abstract: A High-Voltage Stacked Transistor Circuit (HVSTC) includes a stack of power transistors coupled in series between a first terminal and a second terminal. The HVSTC also has a control terminal for turning on an off the power transistors of the stack. All of the power transistors of the stack turn on together, and turn off together, so that the overall stack operates like a single transistor having a higher breakdown voltage. Each power transistor, other than the one most directly coupled to the first terminal, has an associated bipolar transistor. In a static on state of the HVSTC, the bipolar transistors are off. The associated power transistors can therefore be turned on. In a static off state of the HVSTC, the bipolar transistors are conductive (in one example, in the reverse active mode) in such a way that they keep their associated power transistors off.

Abstract: A Super Junction Field Effect Transistor (FET) device includes a charge compensation region disposed on a substrate of semiconductor material. The charge compensation region includes a set of strip-shaped P? type columns, a floating ring-shaped P? type column that surrounds the set of strip-shaped P? type columns, and a set of ring-shaped P? type columns that surrounds the floating ring-shaped P? type column. A source metal is disposed above portions of the charge compensation region. The source metal contacts each of the strip-shaped P? type columns and each of the ring-shaped P? type columns. An oxide is disposed between the floating P? type column and the source metal such that the floating P? type column is electrically isolated from the source metal. The device exhibits a breakdown voltage that is 0.2% greater than if the floating P? type column were to contact the source metal.

Abstract: A Reverse Bipolar Junction Transistor (RBJT) integrated circuit comprises a bipolar transistor and a parallel-connected distributed diode, where the base region is connected neither to the collector electrode nor to the emitter electrode. The bipolar transistor has unusually high emitter-to-base and emitter-to-collector reverse breakdown voltages. In the case of a PNP-type RBJT, an N base region extends into a P? epitaxial layer, and a plurality of P++ collector regions extend into the base region. Each collector region is annular, and rings a corresponding diode cathode region. Parts of the epitaxial layer serve as the emitter, and other parts serve as the diode anode. Insulation features separate metal of the collector electrode from the base region, and from P? type silicon of the epitaxial layer, so that the diode cathode is separated from the base region. This separation prevents base current leakage and reduces power dissipation during steady state on operation.

Abstract: An IGBT includes a floating P well, and a floating N+ well that extends down into the floating P well. A bottom surface of the floating P well has a waved contour so that it has thinner portions and thicker portions. When the device is on, electrons flow laterally from an N+ emitter, and through a first channel region. Some electrons pass downward, but others pass laterally through the floating N+ well to a local bipolar transistor located at a thinner portion of the floating P type well. The transistor injects electrons down into the N? drift layer. Other electrons pass farther through the floating N+ well, through the second channel region, and to an electron injector portion of the N? drift layer. The extra electron injection afforded by the floating well structures reduces VCE(SAT). The waved contour is made without adding any masking step to the IGBT manufacturing process.

Abstract: An IGBT includes a floating P well and a floating N+ well that extends down into the floating P well. A bottom surface of the floating P well has a waved contour with thinner portions and thicker portions. When the device is on, electrons flow laterally from an N+ emitter and through a channel region. Some electrons pass downward, but others pass laterally through the floating N+ well to one of the thinner portions of the floating P type well. The electrons then pass down from the thinner portions into the N? drift layer. Other electrons pass farther through the floating N+ well to subsequent, thinner electron injector portions of the floating P type well and then into the N? drift layer. The extra electron injection afforded by the waved floating well structure reduces VCE(SAT). The waved contour is made without adding any masking step to the IGBT manufacturing process.

Abstract: A trench IGBT includes a floating P well and a floating N+ well that extends down into the floating P well. A bottom surface of the floating P well has a novel waved contour so that it has thinner portions and thicker portions. When the IGBT is on, electrons flow from an N+ emitter, vertically through a channel along a trench sidewall, and to an N? type drift layer. Additional electrons flow through the channel but then pass under the trench, through the floating P well to the floating N+ well, and laterally through the floating N+ well. NPN transistors are located at thinner portions of the floating P type well. The NPN transistors inject electrons from the floating N+ type well down into the N? drift layer. The extra electron injection reduces VCE(SAT). The waved contour can be made without adding any masking step to an IGBT manufacturing process.

Abstract: An AC line filter module includes AC-to-DC rectification circuitry. The rectification circuitry includes four low forward voltage rectifiers coupled together as two high-side rectifiers and two low-side rectifiers, where each low forward voltage rectifier includes an NPN bipolar transistor and a parallel-connected diode. A current splitting pair of inductors splits a return current so that a portion of the current is supplied to the collector of an NPN bipolar transistor that is on, and so that the remainder of the current is supplied to the base of the transistor that is on. Both low-side rectifiers are driven by these current splitting inductors. A pair of base current return diodes provides base current return paths. Due to the use of NPN bipolar transistors and no PNP bipolar transistors, manufacturing cost is reduced and efficiency is improved as compared to an implementation that uses low forward voltage rectifiers having PNP transistors.

Abstract: A Reverse Bipolar Junction Transistor (RBJT) integrated circuit comprises a bipolar transistor and a parallel-connected distributed diode, where the base region is connected neither to the collector electrode nor to the emitter electrode. The bipolar transistor has unusually high emitter-to-base and emitter-to-collector reverse breakdown voltages. In the case of a PNP-type RBJT, an N base region extends into a P? epitaxial layer, and a plurality of P++ collector regions extend into the base region. Each collector region is annular, and rings a corresponding diode cathode region. Parts of the epitaxial layer serve as the emitter, and other parts serve as the diode anode. Insulation features separate metal of the collector electrode from the base region, and from P? type silicon of the epitaxial layer, so that the diode cathode is separated from the base region. This separation prevents base current leakage and reduces power dissipation during steady state on operation.

Abstract: An AC Line Filter/Rectifier Module (ACLF/RM) has a metal housing and an outward appearance of a conventional AC line filter, but the ACLF/RM includes circuitry that performs both EMI filtering and line filtering as well as very efficient AC-to-DC rectification. Rectification circuitry within the ACLF/RM rectifies an AC voltage signal received onto AC input module terminals and outputs a rectified version of the AC voltage signal onto DC output module terminals. The rectification circuitry includes at least one low forward voltage rectifier, where the low forward voltage rectifier includes a bipolar transistor and a diode. Inductive components perform both EMI filtering and line filtering as well as current splitting required to drive the bipolar transistors of the low forward voltage rectifiers. Due to the use of the low forward voltage rectifiers, the AC-to-DC conversion is more efficient than would be case were a conventional diode bridge rectifier employed.

Abstract: A Low Forward Voltage Rectifier (LFVR) includes a bipolar transistor, a parallel diode, and a base current injection circuit disposed in an easy-to-employ two-terminal package. In one example, the transistor is a Reverse Bipolar Junction Transistor (RBJT), the diode is a distributed diode, and the base current injection circuit is a current transformer. Under forward bias conditions (when the voltage from the first package terminal to the second package terminal is positive), the LFVR conducts current at a rated current level with a low forward voltage drop (for example, approximately 0.1 volts). In reverse bias conditions, the LFVR blocks current flow. Using the LFVR in place of a conventional silicon diode rectifier in the secondary of a flyback converter reduces average power dissipation and increases power supply efficiency.

Abstract: A Super Junction Field Effect Transistor (FET) device includes a charge compensation region disposed on a substrate of semiconductor material. The charge compensation region includes a set of strip-shaped P? type columns, a floating ring-shaped P? type column that surrounds the set of strip-shaped P? type columns, and a set of ring-shaped P? type columns that surrounds the floating ring-shaped P? type column. A source metal is disposed above portions of the charge compensation region. The source metal contacts each of the strip-shaped P? type columns and each of the ring-shaped P? type columns. An oxide is disposed between the floating P? type column and the source metal such that the floating P? type column is electrically isolated from the source metal. The device exhibits a breakdown voltage that is 0.2% greater than if the floating P? type column were to contact the source metal.

Abstract: A full bridge rectifier includes four bipolar transistors, each of which has an associated parallel diode. A first pair of inductors provides inductive current splitting and thereby provides base current to/from one pair of the bipolar transistors so that the collector-to-emitter voltages of the bipolar transistors are low. A second pair of inductors similarly provides inductive current splitting to provide base current to/from the other pair of bipolar transistors. In one embodiment, all components are provided in a four terminal full bridge rectifier module. The module can be used as a drop-in replacement for a conventional four terminal full bridge diode rectifier. When current flows through the rectifier module, however, the voltage drop across the module is less than one volt. Due to the reduced low voltage drop, power loss in the rectifier module is reduced as compared to power loss in a conventional full bridge diode rectifier.

Abstract: A switching converter has a self-driven bipolar junction transistor (BJT) synchronous rectifier. The BJT rectifier includes a BJT and a parallel-connected diode, and has a low forward voltage drop. In a first portion of a switching cycle, a main switch is on and the BJT rectifier is off. Current flows from an input, through the main switch, through the first inductor, to an output. Current also flows through the main switch, through the second inductor, to the output. In a second portion of the cycle, the main switch is turned off but the inductor currents continue to flow. Current flows from a ground node, through the BJT rectifier, through the first inductor, to the output. The BJT is on due to the second inductor drawing a base current from the BJT. In one example, the main switch is a split-source NFET that conducts separate currents through the two inductors.

Abstract: An AC-to-DC converter circuit includes DC-to-DC converter that in turn includes a secondary side circuit. The secondary side circuit includes a secondary winding, a pair of bipolar transistor-based self-driven synchronous rectifiers, a pair of current splitting inductors, and an output capacitor. Each of the synchronous rectifiers includes a bipolar transistor and a diode whose anode is coupled to the transistor collector and whose cathode is coupled to the transistor emitter. The current splitting inductors provide the necessary base current to the bipolar transistors at the appropriate times such that the bipolar transistors operate as synchronous rectifiers.

Abstract: A switching converter has a self-driven bipolar junction transistor (BJT) synchronous rectifier. The BJT rectifier includes a BJT and a parallel-connected diode, and has a low forward voltage drop. In a first portion of a switching cycle, a main switch is on and the BJT rectifier is off. Current flows from an input, through the main switch, through the first inductor, to an output. Current also flows through the main switch, through the second inductor, to the output. In a second portion of the cycle, the main switch is turned off but the inductor currents continue to flow. Current flows from a ground node, through the BJT rectifier, through the first inductor, to the output. The BJT is on due to the second inductor drawing a base current from the BJT. In one example, the main switch is a split-source NFET that conducts separate currents through the two inductors.

Abstract: A Low Forward Voltage Rectifier (LFVR) includes a bipolar transistor, a parallel diode, and a base current injection circuit disposed in an easy-to-employ two-terminal package. In one example, the transistor is a Reverse Bipolar Junction Transistor (RBJT), the diode is a distributed diode, and the base current injection circuit is a current transformer. Under forward bias conditions (when the voltage from the first package terminal to the second package terminal is positive), the LFVR conducts current at a rated current level with a low forward voltage drop (for example, approximately 0.1 volts). In reverse bias conditions, the LFVR blocks current flow. Using the LFVR in place of a conventional silicon diode rectifier in the secondary of a flyback converter reduces average power dissipation and increases power supply efficiency.

Abstract: A Low Forward Voltage Rectifier (LFVR) circuit includes a bipolar transistor, a parallel diode, and a capacitive current splitting network. The LFVR circuit, when it is performing a rectifying function, conducts the forward current from a first node to a second node provided that the voltage from the first node to the second node is adequately positive. The capacitive current splitting network causes a portion of the forward current to be a base current of the bipolar transistor, thereby biasing the transistor so that the forward current experiences a low forward voltage drop across the transistor. The LFVR circuit sees use in as a rectifier in many different types of switching power converters, including in flyback, Cuk, SEPIC, boost, buck-boost, PFC, half-bridge resonant, and full-bridge resonant converters. Due to the low forward voltage drop across the LFVR, converter efficiency is improved.