John Jay Dernovsek from 219 Avian Ln, Madison, AL 35758, age 68, Phone: 2567728054

Us Patents

Electronic Ballast With Open Circuit Voltage Control And Cable Compensation
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US Patent:

7098606, Aug 29, 2006
Filed:

Dec 3, 2004
Appl. No.:

11/004625
Inventors:

Qinghong Yu - Salem MA, US
Christopher Radzinski - Huntsville AL, US
Peter Shackle - Rolling Hills Estates CA, US
John Jay Dernovsek - Madison AL, US
Assignee:

Universal Lighting Technologies, Inc. - Madison AL
International Classification:

H05B 37/02
US Classification:

315291, 315224, 315307, 315DIG 7
Abstract:

An electronic ballast uses a voltage sampling circuit and a voltage control circuit to limit the open circuit voltage of the ballast. A lamp voltage sensing circuit is provided that uses a voltage dividing capacitor to accomplish lossless monitoring of the open circuit voltage of the ballast. A resistor placed in series with the sampling capacitor is used to create a voltage that turns a control transistor off and on. The control transistor produces a gating signal trimming signal that a half bridge driver uses to alter the gating signals provided to the inverter transistors of the ballast. A cable compensation circuit is included that minimizes variations in the open circuit voltage due to the connecting and disconnecting of a cable to the ballast by turning the control transistor off and on.

Electronic Ballast With Lossless Snubber Capacitor Circuit
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US Patent:

7098607, Aug 29, 2006
Filed:

Dec 3, 2004
Appl. No.:

11/004667
Inventors:

Qinghong Yu - Salem MA, US
Christopher Radzinski - Huntsville AL, US
John Jay Dernovsek - Madison AL, US
Peter Shackle - Rolling Hills Estates CA, US
Assignee:

Universal Lighting Technologies, Inc. - Madison AL
International Classification:

H05B 37/02
US Classification:

315291, 315224, 315307, 315DIG 7
Abstract:

An improved high input voltage instant start electronic ballast uses a substantially lossless snubber circuit. The substantially lossless snubber circuit is incorporated into the ballast to reduce turn off losses and increase the efficiency of the ballast. The snubber circuit includes two capacitors connected in parallel with respect to the two switching transistors or FETS in the inverter of the ballast. A series-resonant lamp voltage sensing circuit is also provided that uses a voltage dividing capacitor to accomplish lossless monitoring of the open circuit voltage of the ballast. A cable compensation circuit minimizes variations in the open circuit voltage due to the connecting and disconnecting of a cable to the ballast by limiting the turn on times of the transistors during high voltage conditions.

Lossless Circuit For Sampling Of Lamp Voltage
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US Patent:

7098608, Aug 29, 2006
Filed:

Dec 3, 2004
Appl. No.:

11/004668
Inventors:

Qinghong Yu - Salem MA, US
Peter Shackle - Rolling Hills Estates CA, US
John Jay Dernovsek - Madison AL, US
Assignee:

Universal Lighting Technologies, Inc. - Madison AL
International Classification:

H05B 37/02
US Classification:

315291, 315224, 315307, 315DIG 7
Abstract:

An electronic ballast has a resonant tank circuit that includes a tank inductor and a tank capacitor connected in series. Lossless sampling of the output voltage of the electronic ballast is achieved by monitoring the voltage across a sampling capacitor placed in series with the tank capacitor. A resistive and capacitive filter is used to filter the monitored voltage such that it can be accurately received by a microcontroller. A resistor is connected in series with the sampling capacitor to produce an open circuit output voltage control signal that is used by the microcontroller to limit the open circuit output voltage. A cable compensation circuit is utilized to minimize variations in the open circuit voltage due to the connecting and disconnecting of a cable to the ballast output terminals.

High Efficiency 4-Lamp Instant Start Ballast
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US Patent:

7132803, Nov 7, 2006
Filed:

Dec 3, 2004
Appl. No.:

11/004605
Inventors:

Peter Shackle - Rolling Hills Estates CA, US
John Jay Dernovsek - Madison AL, US
Barrie Drew - Toney AL, US
Qinghong Yu - Salem MA, US
Assignee:

Universal Lighting Technologies, Inc. - Madison AL
International Classification:

H05B 37/02
US Classification:

315224, 315291, 315307
Abstract:

An instant-start ballast for a multiple gas discharge lamp fixture has a single half-bridge inverter that is used to drive at least two series resonant output circuits. Each series resonant output circuit is used to drive two gas discharge lamps. A single output voltage limiting circuit is provided with a microprocessor that monitors the combined output voltages of the series resonant output circuits and uses a single voltage limiting transistor to control the output voltages of the circuits. A capacitor is associated with each gas discharge lamp socket in the fixture such that a voltage across the capacitor indicates that a lamp has been installed in the socket associated with the capacitor. The ignition sequence will only be initiated if the capacitor voltages indicate that a lamp has been installed in each socket of a fixture.

Electronic Ballast With Adaptive Lamp Preheat And Ignition
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US Patent:

7239094, Jul 3, 2007
Filed:

Dec 3, 2004
Appl. No.:

11/004646
Inventors:

Christopher Radzinski - Huntsville AL, US
John Jay Dernovsek - Madison AL, US
Qinghong Yu - Salem MA, US
Assignee:

Universal Lighting Technologies, Inc. - Madison AL
International Classification:

H05B 37/02
US Classification:

315307, 315291, 315224, 315DIG 5
Abstract:

An electronic ballast includes a microcontroller with software to provide an adaptive lamp preheat and ignition operation. The microcontroller commands a test frequency from the inverter and detects the frequency response of the resonant output circuit by measuring the voltage across the resonant capacitor. The measured voltages are compared to one or more reference voltages as the frequency is varied to select the optimal inverter frequency. An algorithm or look-up table is used to set the inverter frequencies for the lamp preheat and ignition phases.

Digital Control Of Electronic Ballasts Using Ac Power Lines As A Communication Medium
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US Patent:

7391168, Jun 24, 2008
Filed:

Jan 13, 2006
Appl. No.:

11/332503
Inventors:

John Jay Dernovsek - Madison AL, US
Deepak Shet - Schaumburg IL, US
Brett Bell - Scottsboro AL, US
Assignee:

Universal Lighting Technologies, Inc. - Madison AL
International Classification:

H05B 37/02
G05B 11/01
US Classification:

315291, 34031014
Abstract:

A system for establishing communications between a central lighting controller and a series of electronic dimming ballasts uses an AC power supply line as a communication medium. A MOSFET switched by a control circuit selectively shorts the AC power lines when a rectified version of the power line signal indicates that the power line signal is nearing a zero crossing to create notches in the AC power signal. A simple receiver in each of the ballasts detects the presence or absence of notches in the power signal and interprets the results as digital data indicating a desired dimming level for each of the ballast. The ballasts then adjust their light output accordingly.

Zero Crossing Detection Of Line Voltage/Current Of Variable Amplitude
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US Patent:

7394204, Jul 1, 2008
Filed:

Jan 13, 2006
Appl. No.:

11/332853
Inventors:

Deepak Shet - Schaumburg IL, US
Changsheng Li - Madison AL, US
John Jay Dernovsek - Madison AL, US
Assignee:

Universal Lighting Technologies, Inc. - Madison AL
International Classification:

H05B 37/02
US Classification:

315194, 315199, 315DIG 4
Abstract:

A method and apparatus for detecting a zero crossing or desired phase angle of a power line signal having a variable amplitude uses a ratio between a peak amplitude of the power line signal and the amplitude of the power line signal at a desired phase angle for a known amplitude version of the power line signal to detect when a variable amplitude version of the power line signal is at the desired phase angle or zero crossing. The detection of the phase angle is used to determine if a notch is present in the power line signal. A substantially constant width pulse is generated if a notch is detected regardless of the amplitude of the power line voltage or current. The invention is particularly useful in a lighting system for generating and detecting pulses used to communicate information from a power line communication controller to a series of electronic ballasts over a power line used to power the ballasts. The information can be used to control a dimming function of the ballasts.

Method Of Operating A Resonant Inverter Using Zero Current Switching And Arbitrary Frequency Pulse Width Modulation
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US Patent:

7800928, Sep 21, 2010
Filed:

Dec 6, 2007
Appl. No.:

11/951969
Inventors:

John Jay Dernovsek - Madison AL, US
Steve Mays - Madison AL, US
Assignee:

Universal Lighting Technologies, Inc. - Madison AL
International Classification:

H02M 7/5387
H02M 3/24
US Classification:

363132, 363 98
Abstract:

A method of controlling a series-resonant, half-bridge inverter includes turning off the bottom switch and turning on the top switch the inverter when the current through the resonant inductor crosses the zero axis while the current is increasing, thereby insuring zero voltage switching of the inverter switches and increases the overall switching period so that the actual inverter frequency is closer to the resonant frequency of the series-resonant circuit. Using an on-time control circuit, the method further includes controlling the current delivered to the load (such as a gas discharge lamp) by varying the on-time of the top inverter switch.