Abstract: The invention is related to a driving circuit that provides an operating current for at least one lighting means. The driving circuit comprises an isolated switched converter having a switch (4) controlled by a control circuit (10), wherein a primary side choke (3) is charged when the switch (4) is in its conducting state and the primary side choke (3) is discharged when the control circuit (10) controls the switch (4) in its non-conducting state. The circuit comprises first determining means (13) for monitoring the current through the primary side choke (3), and second determining means (11) for determining a switch-off time, wherein the second determining means (11) comprises an auxiliary winding (12) coupled to a secondary side choke (6) and the second determining means (11) is configured to monitor the voltage across the auxiliary winding (12) for determining a switch-off time.

Abstract: A driver circuit (21) for a light source (20) comprises an input configured for coupling to a power line (19). A control device (24) is configured to control at least one controllable switch (23) to control an output current or output voltage of the driver circuit (21). The control device (24) is configured to modulate a signal onto the power line (19) by setting a switching frequency of the at least one controllable switch (23) in dependence on data to be transmitted by the driver circuit (21; 121, 131) over the power line (19).

Abstract: The invention relates to an operating device (1) for lighting means (8), having a circuit (101) for dividing a rectified alternating voltage to direct voltages of lower levels, wherein the circuit (101) comprises a PFC block comprising a plurality of half bridge converters (102, 103, 104) that are arranged such that the sum of the input voltage drops across the half bridge converters (102, 103, 104) corresponds to the value of the rectified alternating voltage, wherein the circuit (101) is the first active stage in a power supply for the lighting means (8).

Abstract: The invention relates to an operating device (1) for lighting means (8), having a circuit (101) for dividing a rectified alternating voltage to direct voltages of lower levels, wherein the circuit (101) comprises a PFC block comprising a plurality of half bridge converters (102, 103, 104) that are arranged such that the sum of the input voltage drops across the half bridge converters (102, 103, 104) corresponds to the value of the rectified alternating voltage, wherein the circuit (101) is the first active stage in a power supply for the lighting means (8).

Abstract: A converter for supplying current to a light emitting means (8, 9), the converter (6, 7; 10; 90; 100) comprising: an input (11, 12) configured to receive a direct current supply voltage; 10 at least a first controllable switch (21; 41, 43) electrically connected between the input (11, 12) and an inductor (13), and a second controllable switch (22; 42, 44) electrically connected between the input (11, 12) and the inductor (13); a first diode (14) and a second diode (15) connected in series; a first capacitance (16) connected in parallel with the first diode (14) and a second capacitance (17) connected in parallel with the second diode (15); the inductor (13) having a terminal coupled to the at least one controllable switch (21, 22; 41-44) and another terminal coupled to an anode of the first diode (14) and a cathode of the second diode (15); and a control device (20) to control the first controllable switch (21; 41, 43) and the second controllable switch (22; 42, 44), wherein the control device (20) is configu

Abstract: The invention is related to a driving circuit that provides an operating current for at least one lighting means. The driving circuit comprises an isolated switched converter having a switch (4) controlled by a control circuit (10), wherein a primary side choke (3) is charged when the switch (4) is in its conducting state and the primary side choke (3) is discharged when the control circuit (10) controls the switch (4) in its non-conducting state. The circuit comprises first determining means (13) for monitoring the current through the primary side choke (3), and second determining means (11) for determining a switch-off time, wherein the second determining means (11) comprises an auxiliary winding (12) coupled to a secondary side choke (6) and the second determining means (11) is configured to monitor the voltage across the auxiliary winding (12) for determining a switch-off time.

Abstract: The current document is directed to a virtual-reality system, and methods incorporated within the virtual-reality system, that provides a scalable physical volume in which human participants can freely move and assume arbitrary body positions while receiving electronic signals that are rendered to the human participants by virtual-reality rendering appliances to immerse the human participants in a virtual environment. In a described implementation, the virtual-reality system includes multiple networked optical sensors, a computational tracking system, networked virtual-reality engines, and virtual-reality rendering appliances.

Abstract: A converter for supplying current to a light emitting means (8, 9), the converter (6, 7; 10; 90; 100) comprising: an input (11, 12) configured to receive a direct current supply voltage; 10 at least a first controllable switch (21; 41, 43) electrically connected between the input (11, 12) and an inductor (13), and a second controllable switch (22; 42, 44) electrically connected between the input (11, 12) and the inductor (13);a first diode (14) and a second diode (15) connected in series; a first capacitance (16) connected in parallel with the first diode (14) and a second capacitance (17) connected in parallel with the second diode (15); the inductor (13) having a terminal coupled to the at least one controllable switch (21, 22; 41-44) and another terminal coupled to an anode of the first diode (14) and a cathode of the second diode (15); and a control device (20) to control the first controllable switch (21; 41, 43) and the second controllable switch (22; 42, 44), wherein the control device (20) is configur

Abstract: A driver circuit (21) for a light source (20) comprises an input configured for coupling to a power line (19). A control device (24) is configured to control at least one controllable switch (23) to control an output current or output voltage of the driver circuit (21). The control device (24) is configured to modulate a signal onto the power line (19) by setting a switching frequency of the at least one controllable switch (23) in dependence on data to be transmitted by the driver circuit (21; 121, 131) over the power line (19).

Abstract: A power factor correction circuit includes an inductor L1, a diode D1, a switch Q3 and a controller 24. An input voltage Vin is applied to the inductor L1 which is cyclically discharged through the diode D1 by the operation of the switch Q3. The switch Q3 is controlled by the controller 24 which varies the on period of the switch Q3, during which the inductor is charged, for adjusting an output voltage Vbus towards a target value Vbus_target. The method includes obtaining an indication of the inductor L1 reaching a discharged state in response to the switch being in an off state. The controller 24 monitors at least one of the switch on period Ton and the switch off period Toff to identify when the input voltage Vin is an alternating voltage AC input, and when it is likely to be a non-alternating voltage DC input. When a non alternating voltage is detected, steps may be taken to reduce interference.

Abstract: A power factor correction circuit includes an inductor L1, a diode D1, a switch Q3 and a controller 24. An input voltage Vin is applied to the inductor L1 which is cyclically discharged through the diode D1 by the operation of the switch Q3. The method of operation includes: operating a controller 24 to obtain an indication of the voltage across the switch Q3, monitoring the indication of the voltage across the switch Q3 to determine when the inductor L1 reaches a discharged state in response to the switch being in an off state, and the switch Q3 being controlled by the controller 24 to vary the on period of the switch Q3, during which the inductor is charged, for adjusting an output voltage Vbus towards a target value Vbus—target. The controller 24 monitors at least one of the indication of the voltage across the switch Q3 and the ratio of the switch on period Ton to the switch off period Toff for detecting that the input voltage Vin has a low value.

Abstract: A method and circuit for correcting a power factor in an alternating current/direct current power transformer. The circuit has an inductor fed by a rectified AC voltage, and a switch by which the inductor can be charged and discharged by closing and opening the switch, and further has a diode by which the discharge current of the inductor is fed to the output of the circuit. During the discharge phase, a voltage corresponding to the output voltage is measured, and the measured values are stored. It is further determined when the discharge current reaches or crosses the zero line at the end of a discharge phase. Switch-on and switch-off signals for actuating the switch are generated by analyzing the information determined. The switch should not be switched on again until a particular minimum switch-off time has been reached.

Abstract: The application relates to a circuit for operating a light-emitting means, having a half-bridge or full-bridge circuit for providing a supply voltage for the at least one light-emitting means, and a control circuit for the closed-loop control of the operation of the light-emitting means and/or fault identification. A measurement signal which represents the current through the bridge circuit and/or a measurement signal which represents the lamp current and a measurement signal which represents the voltage across the at least one light-emitting means are supplied to the control circuit at the same input.

Abstract: A power factor correction circuit includes an inductor L1, a diode D1, a switch Q3 and a controller 24. An input voltage Vin is applied to the inductor L1 which is cyclically discharged through the diode D1 by the operation of the switch Q3. The method of operation includes: operating a controller 24 to obtain an indication of the voltage across the switch Q3, monitoring the indication of the voltage across the switch Q3 to determine when the inductor L1 reaches a discharged state in response to the switch being in an off state, and the switch Q3 being controlled by the controller 24 to vary the on period of the switch Q3, during which the inductor is charged, for adjusting an output voltage Vbus towards a target value Vbus—target. The controller 24 monitors at least one of the indication of the voltage across the switch Q3 and the ratio of the switch on period Ton to the switch off period Toff for detecting that the input voltage Vin has a low value.

Abstract: A power factor correction circuit includes an inductor L1, a diode D1, a switch Q3 and a controller 24. An input voltage Vin is applied to the inductor L1 which is cyclically discharged through the diode D1 by the operation of the switch Q3. The switch Q3 is controlled by the controller 24 which varies the on period of the switch Q3, during which the inductor is charged, for adjusting an output voltage Vbus towards a target value Vbus—target. The method includes obtaining an indication of the inductor L1 reaching a discharged state in response to the switch being in an off state. The controller 24 monitors at least one of the switch on period Ton and the switch off period Toff to identify when the input voltage Vin is an alternating voltage AC input, and when it is likely to be a non-alternating voltage DC input. When a non alternating voltage is detected, steps may be taken to reduce interference.

Abstract: A method and circuit for correcting a power factor in an alternating current/direct current power transformer. The circuit has an inductance fed by a rectified AC voltage, and a switch by which the inductance can be charged and discharged by closing and opening the switch, and further has a diode by which the discharge current of the inductance is fed to the output of the circuit. During the discharge phase, a voltage Vmon corresponding to the output voltage VBUS is measured, and the measured values are stored. It is further determined when the discharge current reaches or crosses the zero line at the end of a discharge phase. Switch-on and switch-off signals for actuating the switch are generated by analyzing the information determined. The switch should not be switched on again until a particular minimum switch-off time has been reached.

Abstract: The application relates to a circuit for operating a light-emitting means, having a half-bridge or full-bridge circuit for providing a supply voltage for the at least one light-emitting means, and a control circuit for the closed-loop control of the operation of the light-emitting means and/or fault identification. A measurement signal which represents the current through the bridge circuit and/or a measurement signal which represents the lamp current and a measurement signal which represents the voltage across the at least one light-emitting means are supplied to the control circuit at the same input.

Abstract: A system, apparatus and method for providing vehicle information to a vehicle-diagnostic system (VDS) is provided. The VDS may use the vehicle information provided by the system to process vehicle diagnostic data associated with an operation of a vehicle. The system includes a network server being adapted to (i) receive from a vehicle-diagnostic system a first request for particular vehicle information; (ii) provide to an information-retrieval engine the first request; (iii) receive from the information-retrieval engine an indication as to whether the particular vehicle information has been located; (iv) receive from the information-retrieval engine the particular vehicle information; and (v) provide to the vehicle-diagnostic system the particular vehicle information.

Abstract: A method, system and apparatus for decreasing the time frame synchronization and resynchronization in a data communication uses an long frame sync word formed by combining a frame sync word with stuff bits, wherein the stuff bits are necessary for timing adjustments.