Osram Sylvania Inc.

Other

Vipin C Madhani

Alan Adamsky

Andrew Johnsen

Thomas Tessnow

Guy P Bouchard

Charles M Coushaine

Michael D Tucker

Kim Albright

Peter Frey

Bernhard Ertl

Mike Tucker

Andrew O Johnsen

A dual voltage and current control feedback control loop for an optical sensor system. A power supply provides a regulated DC voltage. A current source receives the regulated DC voltage and provides switched current to a light source. A current feedback representative of the current to the light source is provided to the power supply on a feedback path when the current source is driving the light source. A voltage feedback representative of the DC voltage is provided to the power supply on the feedback path when the current source is not driving the light source.

Dual voltage and current control feedback loop for an optical sensor system

A high voltage supply circuit to drive a light source in an optical sensor system. The high voltage supply provides a high voltage output to the light source during the start of an on time for the light source to decrease current rise time through the light source. After the start of the light source on time, the high voltage output is disconnected from the circuit and a current source provides current output to the light source to drive the light source during the remainder of the light source on time.

High voltage supply to increase rise time of current through light source in an optical sensor system

An optical sensor system having a light source comprising a plurality of series connected light emitting diodes (LEDs). The series connected LEDs may be switched at a predetermined frequency.

Optical sensor system including series connected light emitting diodes

A current source circuit to drive a light source in an optical sensor system is disclosed. The current source includes an inductor connected in series with a resistor, and a diode coupled in parallel with the inductor and resistor. The current source is configured to receive a regulated direct current (DC) voltage and to provide the current through the inductor to the light source when a switch is closed, and to divert current through the inductor to the diode when the switch is open.

Current source to drive a light source in an optical sensor system

An LED lamp () has a housing () with an interior wall () defining a cavity (). An LED light source () is positioned in the cavity () and project light in a forward direction. A reflector () having a reflective surface (), a forward opening () and a rear opening () surrounds the light source () and a complex lens () closes the forward opening. The lens () comprises a first optical refractive element () arranged around a peripheral edge () and a second optical refractive element () centrally located on the lens (); the first optical refractive element () including a plurality of flute lenses () and the second optical refractive element () comprising a concavo-convex lens ().

LED lamp module

A high intensity discharge (HID) assembly comprises ballast circuits which includes a micro-controller, and an HID headlamp. In order to deter theft of the HID assembly from a vehicle, the micro-controller communicates with a vehicle computer, checks the VIN of the vehicle, and if the micro-controller does not recognize the VIN, causes the HID headlamp to operate in a flickering power output mode. The ballast circuits include a power control circuit, a lamp current regulator, a 400v regulator, a current sense circuit, a turn-on synchronization circuit, a shut down circuit, and a pulse width modulator.

High intensity discharge lamp ballast with anti-theft operating mode

A circuit for operating a high intensity discharge (HID) lamp includes an H-bridge connected between a common terminal and a power line, and a control circuit connected to the H-bridge. The control circuit includes a transformer having a primary winding connected between the common terminal and a power terminal and a secondary winding connected between the common terminal and the power line, and a current sense resistor connected in series between the secondary winding and the common terminal. The HID lamp is connected to the common terminal and to the second winding so as sense a current across the current sense resistor.

High intensity discharge lamp with current sense resistor

An LED light source () has a housing () with a base (). A central heat conductor () is centrally located within the hollow core () and is formed of a suitable heat-conducting material, such as copper. A cap () is fitted over a second printed circuit board (), and a heat sink () is attached to the base () and in thermal contact with a first printed circuit board (). The heat sink () has a bottom () with an upstanding side wall () terminating in a plurality of fingers (), the fingers () being formed to overlie an upper surface () of the base (). The heat sink () is preferably formed from black-anodized aluminum.

LED bulb

A first vehicle lamp driver circuit for a light emitting diode (LED) array, the LED array having a first string of four LEDs in series and a second string of four LEDs in series. A first LED driver drives the first LED string and a second LED driver drives the second LED string. In a STOP mode of operation, the current to both LED strings is controlled by the LED driver in series with the LED string. In a TAIL mode of operation, the current is provided to only one LED string via a series connected diode and resistor. When there is reduced input voltage, operation of the LED strings is provided by switching circuits that short-out one LED in each LED string. A second vehicle lamp driver circuit comprises a first LED string and a second LED string in series with a control switch having a feedback circuit for maintaining constant current regulation to control the sum of the current in each LED string and reduce switching noise.

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Burlington, MA, United States of America

Vipin C Madhani