Volterra Semiconductor Patent Grants

Apparatus for isolated switching power supply with coupled output inductors

Granted: November 29, 2011
Patent Number: 8068355
A multiphase DC-to-DC power converter has two or more sets of input switches, each set of input switches driving primary windings of at least one associated transformer. Each transformer has one or two secondary windings, the secondary windings feeding power through output switches or rectifiers through an associated output inductor into a common filter. At least two of the output inductors are magnetically coupled.

Start mode in switching regulation

Granted: October 25, 2011
Patent Number: 8044648
A voltage regulator is operated by, during a finite period of a voltage regular start mode having a plurality of current pulses, monotonically increasing the maximum current of the current pulses and a target voltage.

Low profile inductors for high density circuit boards

Granted: October 18, 2011
Patent Number: 8040212
An inductor includes a core formed of a magnetic material and a foil winding wound at least partially around or through at least a portion of the core. A first end of the winding extends away from the core to form an extended output tongue configured and arranged to supplement or serve as a substitute for a printed circuit board foil trace. A second end of the winding forms a solder tab. At least a portion of the extended output tongue and the solder tab are formed at a same height…

Error amplification for current mode control switching regulation

Granted: September 13, 2011
Patent Number: 8018208
A voltage regulator has a switch configured to alternately couple and decouple a voltage source through an inductor to a load, feedback circuitry to generate a feedback current, a current sensor configured to measure the feedback current, and a controller configured to receive the feedback current measurement from the current sensor and, in response thereto, to control a duty cycle of the switch. The feedback circuitry includes an amplifier having a first input configured to receive a…

Voltage regulator with inductor banks

Granted: September 6, 2011
Patent Number: 8014180
A voltage regulator coupled to an unregulated DC input voltage source by an input terminal, and to a load by an output terminal is disclosed. The voltage regulator converts an input voltage at the input terminal to an output voltage at the output terminal. The voltage regulator includes one or more slaves, and each slave includes a switching circuit which serves as a power switch for alternately coupling and decoupling the input terminal to an intermediate node. The voltage regulator…

Heavily doped region in double-diffused source MOSFET (LDMOS) transistor and a method of fabricating the same

Granted: August 16, 2011
Patent Number: 7999318
A transistor includes a source, a drain and a gate. The source includes a p-doped p-body, a p+ region overlapping the p-body, an n+ region overlapping the p-body in proximity to the p+ region, and an n-doped source, heavily double-diffused (SHDD) region, only into the source region of the transistor, the SHDD region having a depth about equal to that of the first n+ region and overlapping the first n+ region. The drain includes a second n+ region and an n-doped shallow drain overlapping…

Multi-turn inductors

Granted: August 9, 2011
Patent Number: 7994888
A multi-winding inductor includes a first foil winding and a second foil winding. One end of the first foil winding extends from a first side of the core and wraps under the core to form a solder tab under the core. One end of the second foil winding extends from a second side of the core and wraps under the core to form another solder tab under the core. Respective portions of each solder tab are laterally adjacent under the magnetic core. A coupled inductor includes a magnetic core…

Flip chip power switch with under bump metallization stack

Granted: August 2, 2011
Patent Number: 7989953
A semiconductor package includes a semiconductor substrate a semiconductor substrate having source and drain regions formed therein, an intermediate routing structure to provide electrical interconnects to the source and drain regions, a dielectric layer formed over the intermediate routing structure, and an under-bump-metallization (UBM) stack. The intermediate routing structure includes an outermost conductive layer, and the dielectric layer has an opening positioned over a portion of…

Method of fabricating a lateral double-diffused MOSFET (LDMOS) transistor and a conventional CMOS transistor

Granted: July 19, 2011
Patent Number: 7981739
A method of fabricating an LDMOS transistor and a conventional CMOS transistor together on a substrate. A P-body is implanted into a source region of the LDMOS transistor. A gate oxide for the conventional CMOS transistor is formed after implanting the P-body into the source region of the LDMOS transistor. A fixed thermal cycle associated with forming the gate oxide of the conventional CMOS transistor is not substantially affected by the implanting of the P-body into the source region of…

Method for making magnetic components with M-phase coupling, and related inductor structures

Granted: June 21, 2011
Patent Number: 7965165
An M phase coupled inductor includes a magnetic core including a first end magnetic element, a second end magnetic element, and M legs disposed between and connecting the first and second end magnetic elements. M is an integer greater than one. The coupled inductor further includes M windings, where each winding has a substantially rectangular cross section. Each one of the M windings is at least partially wound about a respective leg.

Method for making magnetic components with N-phase coupling, and related inductor structures

Granted: March 1, 2011
Patent Number: 7898379
Methods and structures for constructing a magnetic core of a coupled inductor. The method provides for constructing N-phase coupled inductors as both single and scalable magnetic structures, where N is an integer greater than 1. The method additionally describes how such a construction of the magnetic core may enhance the benefits of using the scalable N-phase coupled inductor. The first and second magnetic cores may be formed into shapes that, when coupled together, may form a single…

Method for making magnetic components with N-phase coupling, and related inductor structures

Granted: February 22, 2011
Patent Number: 7893806
Methods and structures for constructing a magnetic core of a coupled inductor. The method provides for constructing N-phase coupled inductors as both single and scalable magnetic structures, where N is an integer greater than 1. The method additionally describes how such a construction of the magnetic core may enhance the benefits of using the scalable N-phase coupled inductor. The first and second magnetic cores may be formed into shapes that, when coupled together, may form a single…

Method of fabricating a lateral double-diffused MOSFET

Granted: February 15, 2011
Patent Number: 7888222
A method of monolithically fabricating an LDMOS transistor with a fabrication process that is compatible with a sub-micron CMOS fabrication process. The specification further describes an LDMOS transistor. The LDMOS transistor is implemented in a first impurity region on a substrate. The LDMOS transistor has a source that includes a second impurity region. The second impurity region is implanted into the surface of the substrate within the first impurity region. Additionally, the LDMOS…

Methods and apparatus for LDMOS transistors

Granted: January 11, 2011
Patent Number: 7868378
An LDMOS transistor includes a gate including a conductive material over an insulator material, a source including a first impurity region and a second impurity region, a third impurity region, and a drain including a fourth impurity region and a fifth impurity region. The first impurity region is of a first type, and the second impurity region is of an opposite second type. The third impurity region extends from the source region under the gate and is of the first type. The fourth…

Method for making magnetic components with N-phase coupling, and related inductor structures

Granted: January 4, 2011
Patent Number: 7864016
Methods and structures for constructing a magnetic core of a coupled inductor. The method provides for constructing N-phase coupled inductors as both single and scalable magnetic structures, where N is an integer greater than 1. The method additionally describes how such a construction of the magnetic core may enhance the benefits of using the scalable N-phase coupled inductor. The first and second magnetic cores may be formed into shapes that, when coupled together, may form a single…

Method and apparatus for multi-phase DC-DC converters using coupled inductors in discontinuous conduction mode

Granted: December 28, 2010
Patent Number: 7859238
A multi-phase, coupled-inductor, DC-DC voltage converter operates in discontinuous conduction mode (DCM) when the system is operated at low output power demand. An embodiment of the converter switches to operating in continuous conduction mode (CCM) when the system is operated at high output power demand. Operation in single-drive and rotating phase DCM operation at low power are described. An alternative embodiment operates in a multiple-drive, rotating-phase, discontinuous conduction…

Voltage regulator with adaptation control

Granted: November 9, 2010
Patent Number: 7830688
A voltage regulator coupled to an unregulated DC input voltage source by an input terminal, and to a load by an output terminal is disclosed. The voltage regulator converts an input voltage at the input terminal to an output voltage at the output terminal. The voltage regulator includes one or more slaves, and each slave includes a switching circuit. During each switching period of the switching circuit, the current for the slave is checked; namely, after the beginning of a low-side…

Voltage regulator with communication ring scheme

Granted: November 2, 2010
Patent Number: 7825643
A voltage regulator coupled to an unregulated DC input voltage source by an input terminal, and to a load by an output terminal is disclosed. The voltage regulator converts an input voltage at the input terminal to an output voltage at the output terminal. The voltage regulator includes a master controller and one or more slaves, and the master controller and each slave can communicate using a ring communication scheme. A command generated by the master controller can be passed from the…

Analog current command and settable slopes in voltage regulator

Granted: September 14, 2010
Patent Number: 7795850
A voltage regulator coupled to an unregulated DC input voltage source by an input terminal, and to a load by an output terminal is disclosed. The voltage regulator converts an input voltage at the input terminal to an output voltage at the output terminal. The voltage regulator includes one or more slaves, and each slave includes a switching circuit which serves as a power switch for alternately coupling and decoupling the input terminal to an intermediate node. Each slave can include a…

Method for making magnetic components with N-phase coupling, and related inductor structures

Granted: August 10, 2010
Patent Number: 7772955
Methods and structures for constructing a magnetic core of a coupled inductor. The method provides for constructing N-phase coupled inductors as both single and scalable magnetic structures, where N is an integer greater than 1. The method additionally describes how such a construction of the magnetic core may enhance the benefits of using the scalable N-phase coupled inductor. The first and second magnetic cores may be formed into shapes that, when coupled together, may form a single…