ROBERT M CALLANAN
Accountancy in Raleigh, NC

2013026, Oct 10, 2013

Apr 4, 2012

13/438927

Robert J. Callanan - Raleigh NC, US

CREE, INC. - Durham NC

H03K 17/06

327109

A circuit, which includes a high voltage driver, is disclosed. The high voltage driver includes a P-type field effect transistor (PFET) and a source bias circuit. The source bias circuit receives a low voltage input signal and applies a direct current (DC) bias to the low voltage input signal to provide a DC biased signal. The PFET has a first source, a first gate, and a first drain. The first source receives the DC biased signal. The first gate receives a first low voltage DC supply signal. The first drain provides a high voltage output signal based on the DC biased signal and the first low voltage DC supply signal. In this regard, the high voltage driver receives and translates the low voltage input signal to provide the high voltage output signal.

8218345, Jul 10, 2012

Mar 20, 2009

12/408304

Robert Joseph Callanan - Raleigh NC, US
Fatima Husna - Morrisville NC, US

Cree, Inc. - Durham NC

H02M 7/217

363 89, 363127

A rectifier circuit can include an input circuit and first and second silicon carbide (SiC) bipolar junction transistors (BJTs). The input circuit is configured to respond to an alternating current (AC) input signal by generating a first pair of opposite polarity AC signals and a second pair of opposite polarity AC signals. The first pair of AC signals has a greater voltage range than the second pair of AC signals. The first and second SiC BJTs each include an input terminal connected to receive a different one of the second pair of opposite polarity AC signals, a base terminal connected to receive a different one of the first pair of opposite polarity AC signals, and an output terminal connected to a rectified signal output node of the rectifier circuit. The input circuit is further configured to control the first and second SiC BJTs through the first and second pairs of opposite polarity AC signals to forward bias the first SiC BJT while reverse biasing the second SiC BJT during a first half cycle of the AC input signal and to reverse bias the second SiC BJT while forward biasing the second SiC BJT during a second half cycle of the AC input signal.

8294507, Oct 23, 2012

May 8, 2009

12/437929

Qingchun Zhang - Cary NC, US
James Theodore Richmond - Hillsborough NC, US
Robert J. Callanan - Raleigh NC, US

Cree, Inc. - Durham NC

H03K 17/72

327440, 327471, 327474, 327475

An electronic device includes a wide bandgap thyristor having an anode, a cathode, and a gate terminal, and a wide bandgap bipolar transistor having a base, a collector, and an emitter terminal. The emitter terminal of the bipolar transistor is directly coupled to the anode terminal of the thyristor such that the bipolar transistor and the thyristor are connected in series. The bipolar transistor and the thyristor define a wide bandgap bipolar power switching device that is configured to switch between a nonconducting state and a conducting state that allows current flow between a first main terminal corresponding to the collector terminal of the bipolar transistor and a second main terminal corresponding to the cathode terminal of the thyristor responsive to application of a first control signal to the base terminal of the bipolar transistor and responsive to application of a second control signal to the gate terminal of the thyristor. Related control circuits are also discussed.

2012007, Mar 29, 2012

Jul 15, 2010

12/837092

Robert Joseph Callanan - Raleigh NC, US

G05F 3/08

323311

A power converter circuit includes a storage component, a rectifier component comprising a first field effect transistor and having first and second bias states, and a switch including a second field effect transistor having first and second operational states. The first and second field effect transistors are High Electron Mobility Transistors (HEMTs).

2013024, Sep 26, 2013

May 14, 2013

13/893998

Robert J. Callanan - Raleigh NC, US
Henry Lin - Chapel Hill NC, US

Cree, Inc. - Durham NC

H01L 29/16, H01L 27/06

257 77, 257288

The present disclosure relates to a power module that has a housing with an interior chamber and a plurality of switch modules interconnected to facilitate switching power to a load. Each of the plurality of switch modules comprises at least one transistor and at least one diode mounted within the interior chamber and both the at least one transistor and the at least one diode are majority carrier devices, are formed of a wide bandgap material system, or both. The switching modules may be arranged in virtually any fashion depending on the application. For example, the switching modules may be arranged in a six-pack, full H-bridge, half H-bridge, single switch or the like.

2011001, Jan 27, 2011

Jul 21, 2009

12/506610

Robert Callanan - Raleigh NC, US

H02M 7/06, H03K 17/687

363126, 327427

Provided is a rectifier circuit that includes a depletion mode semiconductor having an output connected to a rectified signal output node of the rectifier circuit and a hot carrier semiconductor diode having a cathode connected to a source node of the depletion mode semiconductor and an anode connected to a gate node of the depletion mode semiconductor. The rectifier may include an alternating current (AC) input node that is connected to the anode of the hot carrier semiconductor diode and the gate node of the depletion mode semiconductor and that is configured to receive an AC input signal.

8354690, Jan 15, 2013

Aug 31, 2009

12/550574

Robert J. Callanan - Raleigh NC, US
Qingchun Zhang - Cary NC, US

Cree, Inc. - Durham NC

H01L 29/74

257121, 257124, 257E29211, 257E29212

Provided is a semiconductor bistable switching device that includes a thyristor portion including an anode layer, a drift layer, a gate layer and a cathode layer, the gate layer operable to receive a gate trigger current that, when the anode layer is positively biased relative to the cathode layer, causes the thyristor portion to latch into a conducting mode between the anode and the cathode. The device also includes a transistor portion formed on the thyristor portion, the transistor portion including a source, a drain and a transistor gate, the drain coupled to the cathode of the thyristor portion.

2012003, Feb 9, 2012

Aug 4, 2010

12/850098

Robert J. Callanan - Raleigh NC, US

Cree Inc. - Durham NC

H03K 17/56, H01H 71/00

327419, 200 5 A

A circuit breaker is provided that includes primary and secondary paths that extend between first and second terminals. The primary path extends between the first and second terminals and through a first switch. The secondary path extends between the first and second terminals and through the second switch and a semiconductor switching element. During normal operation, a control system maintains the first and second switches in closed position and the semiconductor switching element in blocking state. When a fault condition occurs in the load current, the control system detects the fault condition and sets the semiconductor switching element to conducting state. The control system then sets the first switch to open position such that the load current flows between the first and second terminals through the secondary path. The control system then sets the second switch to open position and the semiconductor switching element to blocking state.