Operating circuit, operating device, lighting system and method for operating at least one light-emitting diode

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Patent office

description

OPERATING WIRING, OPERATING DEVICE, LIGHTING SYSTEM AND PROCEDURE

TO OPERATE AT LEAST ONE LIGHT DIODE

The invention relates to operating circuits for lighting means. The invention relates in particular to an operating circuit for supplying a light-emitting diode (LED) or several LEDs, which is set up for connection to a direct voltage (DC) bus in order to be supplied with a DC supply voltage, as well as operating devices and systems that include such an operating circuit , and methods for operating at least one light emitting diode.

With the increasing spread of light sources such as LEDs, which can be arranged, for example, on an LED module, operating circuits for such light sources continue to gain in importance. Operating circuits are mainly used to provide a desired energy supply for the lighting means. Operating circuits can include a converter, for example, in order to set an LED current to a setpoint value. Additional functions can be integrated into the operating circuit.

To simplify and save costs, it is possible to provide a DC voltage source that generates a DC supply voltage and makes it available to an operating circuit or several operating circuits via a DC bus. The source can, for example, be a central unit which comprises an AC / DC converter and generates the DC supply voltage. The operating circuits are provided separately from the central unit. The operating circuits are coupled to the central unit via a DC bus. Operating circuits for light-emitting diodes that are supplied with a DC supply voltage can also be used in numerous other scenarios, for example if the operating circuit is temporarily fed by a local DC voltage source, as can be the case in an emergency lighting operating state, or if the operating circuit is connected to a photovoltaic module.

The operating circuit can have an integrated semiconductor circuit which controls the operating circuit. For this purpose, the integrated semiconductor circuit can switch a switch of a converter or other current regulator, for example.

In order to be able to implement various control functions, such as brightness and / or color control, and / or to enable the transmission of safety-related or other information, it is desirable that operating circuits of this type are set up for communication.

The invention is based on the object of specifying devices and methods that allow communication to and / or from operating circuits for at least one light-emitting diode and which can be implemented with little effort. The invention is based in particular on the object of specifying such methods and devices in which an operating circuit which is set up for coupling to a DC supply voltage enables unidirectional or bidirectional communication with little additional effort.

According to embodiments of the invention it is provided that a receiving unit for receiving digital light control signals according to a predetermined protocol, preferably according to the DALI standard, is present. Furthermore, a modulator can be present for modulating the control signals onto the DC supply voltage. The modulator can modulate the control signals onto the DC supply voltage as a function of the current level of the digital light control signals received by the receiving unit. The modulator can modulate a control signal with a high level when the digital light control signal received by the receiving unit has a high level. The modulator can modulate a control signal with a low level when the digital light control signal received by the receiving unit has a low level.

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A lighting system according to an embodiment comprises a source for the DC supply voltage and the operating circuit according to an embodiment. The source for the DC supply voltage can be, for example, a central unit which is connected on the input side to an AC voltage source and which can comprise an inverter, a power factor correction circuit and a DC / DC converter. The source for the DC supply voltage can also be a battery, which can be provided remotely from the operating circuit or which can be provided locally on the operating circuit. The receiving unit can be integrated into the source.

[0009] The operating circuit is connected to the source for the DC supply voltage via a DC bus.

Several operating circuits according to exemplary embodiments can be connected to the DC bus.

A PLC modulator for generating the modulated control signals can be integrated into the central unit or can be provided separately from the central unit. The central unit can for example comprise a DC output circuit with the PLC modulator. Such communication is also referred to in technology as PLC (“Power Line Communication”).

[0012] The configuration of the operating circuit for a PLC via a DC bus means that additional signal lines can be dispensed with. This reduces the effort involved in installing the operating circuit.

According to embodiments of the invention it is provided that an integrated semiconductor circuit of an operating circuit is both set up to perform control or regulating functions, and is set up to transmit the control signals that are modulated onto the DC supply voltage and demodulated by a demodulator, read out and / or to send signals to the demodulator.

The demodulator can be designed to modulate signals received from the integrated semiconductor circuit onto the DC supply voltage.

Such an operating circuit, which is used in exemplary embodiments, thus comprises a demodulator for communication via the supply lines, which are designed as a DC bus, and an integrated semiconductor circuit to perform control or regulating functions.

The demodulator takes over the demodulation and / or modulation of PLC signals and thus acts as a PLC demodulator or as a PLC modulator.

According to further embodiments of the invention it is provided that an integrated semiconductor circuit of an operating circuit is both set up to perform control or regulating functions and is set up to read out and / or to control signals that are modulated onto the DC supply voltage To modulate signals to the DC supply voltage. Such an integrated semiconductor circuit can thus have a demodulator integrated therein for communication via the supply lines, which are designed as a DC bus.

If the demodulator is integrated into the integrated semiconductor circuit, it is in particular not necessary to use two separate semiconductor chips, one of which carries out the PLC demodulation and the other of which controls or regulates the operating circuit. This not only reduces the space required for the operating circuit, but also the costs.

An operating circuit for at least one light emitting diode according to one embodiment is set up to receive a DC supply voltage and to provide an LED current for the at least one light emitting diode. The operating circuit comprises an integrated semiconductor circuit for controlling the operating circuit. The integrated semiconductor circuit is set up to read out control signals demodulated from the DC supply voltage by the demodulator.

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[0020] The operating circuit can comprise a converter circuit with at least one controllable switch. The converter circuit can be a step-down converter (which is also referred to in technology as a buck converter), a step-up converter (which is also referred to in technology as a boost converter), an inverse converter (which is also referred to in technology as a buck-boost converter) or a Flyback converter (also referred to in the art as a flyback converter). The operating circuit can comprise a linear current regulator.

The integrated semiconductor circuit can be set up to control the controllable switch as a function of the control signals read out. The integrated semiconductor circuit can be set up to determine switching times for the controllable switch at which the controllable switch is switched on or off.

The integrated semiconductor circuit can be set up to switch the controllable switch depending on the control signals read out by the demodulator. A switching frequency of the controllable switch can be set by the integrated semiconductor circuit as a function of the control signals read out by the demodulator. Alternatively or additionally, switch-on times for switching on the controllable switch and / or switch-off times for switching off the controllable switch can be set as a function of the control signals read out. The control signals read out can define at least one parameter of the converter circuit controlled by the integrated semiconductor circuit. For example, the control signals read out can define a dimming level and thus a change in the LED current. The control signals can also define further parameters, for example the duration and / or the time interval between pulse packets for pulse width dimming.

At least one further parameter of the operation of the converter circuit can be user-defined by means of circuit elements coupled to the integrated semiconductor circuit.

For example, the operating circuit can have a user-defined settable resistance, a user-defined settable capacitance or some other element that can be read out by the integrated semiconductor circuit. For example, different resistance values ​​or capacitance values ​​can be set in order to define different LED currents or output voltages of the operating circuit.

[0025] The converter circuit can be a current regulator. The integrated semiconductor circuit can be set up to control the converter circuit in such a way that a time average value of the LED current is regulated to a target value.

The integrated semiconductor circuit can have a connection which is connected to a controllable switch of the converter circuit.

[0027] The integrated semiconductor circuit can comprise a controllable switch of the converter circuit. The integrated semiconductor circuit can also comprise a driver circuit for the controllable switch of the converter circuit.

The integrated semiconductor circuit can be set up to monitor an operating state of the operating circuit and / or the at least one light-emitting diode. The integrated semiconductor circuit can be designed to send a signal to the demodulator as a function of a diagnosis of the operating state and the demodulator can be designed to modulate the signal onto the DC supply voltage in order to transmit it via the DC bus. Examples of such operating states are an error state of the operating circuit.

Alternatively or in addition, the demodulator can be set up to monitor an output signal of a sensor. The demodulator can be set up to modulate the signal onto the DC supply voltage as a function of the output signal of the sensor in order to supply information about a measured value recorded with the sensor via the DC bus

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Examples of such sensors include temperature sensors that detect a temperature on an operating device or an LED module, or brightness sensors.

The operating circuit and an LED module can be integrated in a common housing.

The operating circuit can be integrated into an operating device which comprises outputs for connection to an LED module.

An operating device according to an exemplary embodiment comprises the operating circuit according to an exemplary embodiment for providing an LED current for at least one light-emitting diode.

A method for operating at least one light-emitting diode according to one embodiment uses an operating circuit that receives a DC supply voltage and provides an LED current for the at least one light-emitting diode. Digital light control signals can be received according to a specified protocol, preferably according to the DALI standard, and the control signals can be modulated onto the DC supply voltage by means of a modulator depending on the current level of the received digital light control signals.

The operating circuit comprises a demodulator and a semiconductor integrated circuit. The demodulator reads out control signals modulated onto the DC supply voltage and forwards them to the integrated semiconductor circuit. The integrated semiconductor circuit controls the operating circuit as a function of the control signals read out.

The control of the operating circuit can include controlling a controllable switch of the operating circuit for providing the LED current.

The operating circuit used in the method can be the operating circuit according to an embodiment.

In the devices, systems and methods according to exemplary embodiments, the control signals that are demodulated and read out by the integrated semiconductor circuit can include control commands encoded in binary sequences. The control commands can include commands for starting, for dimming, for initiating emergency lighting operation, for ending emergency lighting operation and / or for switching off the operating circuit. The control commands can comprise a binary sequence which is coded in the control signal.

The control signal modulated onto the DC supply voltage can be an alternating voltage (AC) signal that is modulated onto the DC supply voltage. The AC signal can have an amplitude that is small compared to the DC supply voltage. The information can be modulated onto the DC supply voltage by modulating the received control signals depending on the current level of the digital light control signals received by the receiving unit. The modulator can modulate a control signal with a high level when the digital light control signal received by the receiving unit has a high level. The modulator can modulate a control signal with a low level when the digital light control signal received by the receiving unit has a low level.

In the devices, systems and methods according to exemplary embodiments, the control signal can be addressed to the operating circuit or to a group of operating circuits. In this way, targeted control can be achieved via the DC bus if several operating circuits are connected to the DC bus.

If the demodulator is set up to modulate a signal to the DC supply voltage for transmitting information from the operating circuit, information can also be encoded by modulation with the characteristic according to the predetermined protocol of the control signal.

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In the devices, systems and methods according to exemplary embodiments, external circuit components can be connected to the semiconductor integrated circuit in order to

Set operating parameters. For example, different operating parameters, for example different LED currents or different output voltages, can be set using settable resistance values ​​or other elements.

In devices, systems and methods according to exemplary embodiments, a unidirectional or bidirectional PLC can be implemented with an operating circuit for at least one light-emitting diode which is set up for a connection to a DC bus. In addition to controlling a current regulator, the integrated semiconductor circuit can also demodulate control signals transmitted in the PLC.

In devices, systems and methods according to exemplary embodiments, the semiconductor integrated circuit can be a microcontroller or a controller. The integrated semiconductor circuit can also be an application-specific special circuit (ASIC), a microprocessor or a processor.

The invention is explained below with reference to the figures using preferred embodiments. In the figures, identical reference characters denote identical elements.

FIG. 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

FIG. 7 shows a system with an operating circuit according to an exemplary embodiment, shows an operating circuit according to an exemplary embodiment.

shows an operating circuit according to a further embodiment, illustrates a transmission of control signals via a DC bus. shows a system with an operating circuit according to an embodiment, shows an operating circuit according to a further embodiment.

shows an operating circuit according to a further embodiment.

FIG. 1 shows an illustration of a system 1 which comprises an operating circuit 10 for at least one light emitting diode (LED) 5. The system comprises a source 2 which is set up to provide a DC supply voltage Vdc. A DC bus 3 connects the source 2 for the DC supply voltage to an input of the operating circuit 10. In order to transmit control signals in a PLC to the operating circuit 10, a PLC modulator 4 is coupled to the DC bus. Even if the PLC modulator 4 is shown as a separate component in FIG. 1, the PLC modulator 4 can for example be integrated into the source 2 for the DC supply voltage. The PLC modulator 4 can be provided in a DC output circuit of the source 2. The source 2 for the DC supply voltage can be provided remote from the operating circuit 10. The source 2 for the DC supply voltage can, however, also be provided locally at the operating circuit 10, for example if a battery provides the DC supply voltage, as can be the case in emergency lighting operation.

The PLC modulator 4 is connected to a receiving unit 30. In this example, the receiving unit 30 is designed as a DALI interface 30. The DALI interface 30 is shown here by way of example as an interface for receiving digital light control signals in accordance with a specified protocol. The interface 30 can alternatively be designed, for example, to receive digital light control signals according to another protocol for wired or wireless transmission, for example for reception according to the DMX protocol, the Bluetooth protocol, the Zigbee protocol or according to the IPv6 protocol.

The PLC modulator 4 can have a microcontroller.

The receiving unit 30 is used to receive digital light control signals according to a predetermined protocol. In this example, the receiving unit 30 for light control signals is designed according to the DALI standard. The PLC modulator 4 recognizes the Emp5 / 16

AT 14 743 U1 2016-05-15 jwfcistamt catching unit 30 received light control signals and modulates the control signals onto the DC bus 3 as a function of these. The PLC modulator 4 modulates the control signals onto the DC bus 3 as a function of the current level of the digital light control signals received by the receiving unit 30.

In FIG. 1, only one operating circuit 10 with assigned LEDs 5 is shown. However, several operating circuits 10, as will be described in detail below, can be connected to the DC bus 3.

The operating circuit 10 is set up in such a way that it generates an LED current for the LEDs 5. The operating circuit 10 can comprise a current regulator. The current regulator can comprise a DC / DC converter 12 which is controlled by an integrated semiconductor circuit 11. The DC / DC converter 12 can be, for example, a step-down converter, a step-up converter, an inverse converter or a flyback converter. A linear current regulator can be used.

The integrated semiconductor circuit 11 can be set up to define an operating point of the current regulator. The integrated semiconductor circuit 11 can be set up to control the current regulator such that a desired LED current is provided to the LEDs 5. The configuration of the integrated semiconductor circuit 11 can be different depending on the configuration of the DC / DC converter 12. For a DC / DC converter which includes a controllable switch, as is shown schematically in FIG. 1, the integrated semiconductor circuit 11 can be set up to control the controllable switch.

The integrated semiconductor circuit 11 can, for example, determine switch-on times at which the controllable switch is switched on and / or switch-off times at which the controllable switch is switched off, and control the controllable switching means accordingly.

The semiconductor integrated circuit 11 is connected to a PLC demodulator 19. The PLC demodulator 19 is designed to read out a control signal modulated onto the DC supply voltage on the DC bus 3. The PLC demodulator 19 can be set up to fulfill the function of a PLC modulator. The PLC demodulator 19 can read out the control signals received via the DC bus 3 and forward them to the integrated semiconductor circuit 11. The controllable switch of the DC / DC converter 12 can be controlled as a function of a control signal received via the DC bus 3.

Various control signals can be transmitted over the DC bus. The PLC demodulator 19 can read a control signal on the DC bus 3 and forward it to the integrated semiconductor circuit 11, which controls the current regulator and, for example, switches the controllable switch of the DC / DC converter, with which a control command to start the operating circuit can be transmitted becomes. In response to this, the semiconductor integrated circuit 11 can control the DC / DC converter 12 in such a way that an LED current for supplying the LEDs 5 is generated. The PLC demodulator 19 can alternatively or additionally read out a control signal on the DC bus 3 and forward it to the integrated semiconductor circuit 11, with which a control command for switching off the operating circuit is transmitted. In response to this, the integrated semiconductor circuit 11 can control the DC / DC converter 12 in such a way that an LED current for supplying the LEDs 5 is no longer generated. The PLC demodulator 19 can alternatively or additionally read out a control signal on the DC bus 3, with which a control command for dimming is transmitted, which can include a dimming level. In response to this, the semiconductor integrated circuit 11 can control the DC / DC converter 12 so that the current for dimming the LED is decreased or increased.

The PLC demodulator 19 can alternatively or additionally read out a control signal on the DC bus 3 with which a control command for emergency lighting is transmitted. In response to this, the integrated semiconductor circuit 11 can control the DC / DC converter 12 such that a time average value of the LED current is reduced for emergency lighting. The corresponding control commands can be generated by the PLC modulator 4.

The control signals can be coded in a sequence of binary values, the characters 6/16

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Patent office teristics of the transmitted control signals, in particular the bit sequence and the data rate, correspond to the DALI protocol. Various modulation techniques can be used in the system 1. AC signals with a predetermined amplitude and predetermined frequency are preferably generated by the PLC modulator 4 and read out by the PLC demodulator 19. The frequency of the AC signals can have a fixed value. The AC signals can be high-frequency AC signals. The amplitude of the AC signals can be small compared to the DC supply voltage. For example, the amplitude of the modulated control signals can be less than 10% or less than 5% of the DC supply voltage. The AC signals can be square wave signals, sinusoidal signals or triangular signals or have other signal shapes. The control signals are preferably encoded in such a way that a light control signal in accordance with the DALI standard, as received by the receiving unit 30, is modulated onto the DC bus 3 as a powerline signal (PLC signal).

The PLC demodulator 19 can be a microcontroller or controller. Other configurations are possible. For example, the PLC demodulator 19 can be a microprocessor, a processor or an application-specific special circuit.

The semiconductor integrated circuit 11 can be a microcontroller or controller. Other configurations are possible. For example, the integrated semiconductor circuit 11 can be a microprocessor, a processor or an application-specific special circuit.

The PLC modulator 4 is, for example, also designed to receive the signals sent out by the PLC demodulator 19 and output them as a kind of return channel to the receiving unit 30, whereby the receiving unit 30 sends out these signals as return signals as digital light control signals according to a predetermined protocol can.

FIG. 2 shows an operating circuit 10 according to an exemplary embodiment. According to this exemplary embodiment, the PLC demodulator 19 and the integrated semiconductor circuit 11 are integrated in one block, for example having a common microcontroller.

An input 13 is set up for a connection to the DC bus 3. The DC / DC converter can be designed, for example, as a step-down converter and comprises a controllable switch 21, a diode 22, an inductance 23 and a capacitor 24. The capacitor 24 is provided as an output capacitance parallel to the outputs 14 of the operating circuit 10. When the controllable switch 21 is on, energy is stored in the inductance 23, which is discharged via the diode 22 when the controllable switch 21 is off. Even if a step-down converter is shown by way of example, other converter topologies can also be used, such as step-up converters, flyback converters or inverse converters.

The controllable switch 21 can be designed as a power switch. The controllable switch can be a transistor with an insulated gate electrode, for example a MOSFET. The integrated semiconductor circuit 11/19 defines an operating point of the current regulator during operation. The integrated semiconductor circuit 11/19 can control the controllable switch 21 in such a way that an LED current can be regulated to a target value by switching it on and off.

As shown in FIG. 2, the integrated semiconductor circuit 11/19 has an output 15 which is connected to the controllable switch 21. The output 15 can be connected to a gate connection of the controllable switch 21.

A driver circuit for the controllable switch 21 can be integrated into the integrated semiconductor circuit 11/19. The controllable switch 21 is controlled as a function of control signals which are modulated onto the DC supply voltage and which are read out by the integrated semiconductor circuit 11/19.

In addition to control by the PLC via the DC bus, the operating circuit 10 can also be set up in such a way that operating parameters can be set by user-defined circuit elements of the operating circuit, as shown in FIG.

FIG. 3 shows an operating circuit 10 according to an exemplary embodiment in which the PLC demodulator 19 is also integrated into the integrated semiconductor circuit 11. With this one

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In the exemplary embodiment, the integrated semiconductor circuit 11 is coupled to at least one circuit element 15, 16 with which the operating parameters of the operating circuit 10 can be set.

For example, a maximum LED current, a forward voltage of the LEDs 5 or another operating parameter can be set via a resistor 16 or a capacitor 15.

The resistor 16 and / or the capacitor 15 can be designed in such a way that it can be set manually to different values. This allows a user-defined configuration of the operating circuit 10 for use with the LED module connected to it. The integrated semiconductor circuit 11 can be set up to read out the user-defined operating parameters as a function of the at least one circuit element 15, 16 and to control the DC / DC converter as a function thereof. Control commands can be received via the DC bus and evaluated by the integrated semiconductor circuit 11, for example in order to switch the operating circuit 10 on or off, to initiate a dimming process or to initiate an emergency lighting operation.

FIG. 4 shows an example of the transmission of control signals via the DC bus. If no data is transmitted in an interval 31, a bus voltage on the DC bus has a value 41 which corresponds to the DC supply voltage Vdc.

When receiving digital light control signals by the receiving unit 30 according to a predetermined protocol, the PLC modulator 4 detects the light control signals received by the receiving unit 30 and modulates the control signals onto the DC bus 3 as a function of these. To transmit a control command, an AC signal 42, 44 can be modulated onto the bus voltage. The corresponding PLC modulator 4 for modulating the control signal can be provided, for example, in a central unit of the system 1 or can be arranged in another operating device for a light source. Control signals or other information can be encoded in the amplitude of the AC signals. The modulated AC signals 42, 44 exemplarily show a modulation in which the first modulated AC signal 42 encodes a first binary value. A second modulated AC signal 44, which differs in the bit sequence from the first modulated AC signal 42, can encode a second binary value. The high-frequency modulation of the AC signals 42, 44 can take place in the form of square-wave signals; other signal forms can also be used, for example sinusoidal or triangular signals. In an interval 33 between the intervals 32, 34 in which the AC signals 42, 44 are modulated, the bus voltage again has a value 43 which is equal to the DC supply voltage.

The PLC modulator 4 can modulate the control signals 42, 44 onto the DC supply voltage 41 as a function of the current level of the digital light control signals received by the receiving unit 30. The modulator 4 can modulate a control signal 42, 44 of a bit sequence of high and low levels, corresponding to the bit sequence of the digital light control signal received by the receiving unit 30.

In the operating circuit 10 according to an exemplary embodiment, the integrated semiconductor circuit 11 can be controlled via the modulated AC signals 42, 44 received by the PLC demodulator 19. Optionally, it is not necessary to use a separate demodulator 19 between the DC bus 3 and the integrated semiconductor circuit 11, but the demodulator 19 can be integrated into the integrated semiconductor circuit 11.

FIG. 5 shows a system 1 according to an exemplary embodiment in which several operating circuits 10 are connected to the DC bus 3.

The system 1 has a source for the DC supply voltage which comprises a central processing unit 60. The central unit 60 is set up to generate a DC supply voltage and to supply the operating circuits 10 with energy via a DC bus 3. Elements such as a rectifier and a power factor correction circuit 62, which conventionally would have to be provided separately in each of a plurality of LED converters, can be present in the central unit 60 and then no longer have to be separately in the different ones

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Lamp operating devices are used. The central unit 60 can include a DC / DC converter 64 with electrical isolation, with which electrical isolation is achieved by a potential barrier 65. For example, a SELV (“Separated Extra Low Voltage”) area can be separated by the potential barrier 65 from an input side of the central unit 60, which is connected to an AC voltage source 61, typically the mains voltage. An output 67 of the central unit 60 is connected to the DC bus 3. A receiving unit 90 can be integrated in the central unit 60 and is used to receive digital light control signals. A PLC modulator 66 is integrated with the receiving unit 90 and can be integrated into the central unit 60. The PLC modulator 66 can be present in a DC output circuit of the central unit 60, for example.

Other configurations of the source for the DC supply voltage on the DC bus 3 can be used. For example, the DC supply voltage can also be provided by a battery or a photovoltaic element.

The operating circuits 10 and the LED modules with the LEDs connected to them in each case can be configured in different ways. For example, the operating circuit 10 can be arranged in an operating device 70 with a housing which has output connections for connection to the LED module 72. An input 71 of the operating device 70 is connected to the DC bus 3.

The operating circuit 10 and the LED module with LEDs 5 supplied by it can also be arranged in a common housing 80. The operating circuit 10 and the LED module can have a common carrier. An input 81 of the operating circuit 10 is connected to the DC bus 3. The operating circuit 10 includes the PLC demodulator 19 (not shown here).

Further modifications of the operating circuit 10 can be implemented in further exemplary embodiments.

FIG. 6 shows an operating circuit 10 according to a further exemplary embodiment, in which the controllable switch 21 of the DC / DC converter 21 is also integrated into the integrated semiconductor circuit 11. The semiconductor integrated circuit 11 may include the PLC demodulator 19. The integrated semiconductor circuit 11 can also comprise a driver circuit for the controllable switch 21. The controllable switch 21 can be a power switch. The controllable switch 21 can comprise a MOSFET in the integrated semiconductor circuit 11.

The integrated semiconductor circuit 11 can comprise an output 18 which is connected to an inductance 23. The output 18 can be connected to a node between the diode 22 and the inductance 23 of the DC / DC converter.

The operating circuits according to various exemplary embodiments can be set up not only for unidirectional communication to the corresponding operating circuit, but also for bidirectional communication or for unidirectional communication in which information is transmitted from operating circuit 10. Examples of such information include diagnostic information that can indicate irregular operating states or fault shutdowns.

Further examples of such information include the transmission of measured values ​​that are recorded with a sensor in an operating device or an LED module.

FIG. 7 shows an example of an operating circuit 10 in which the integrated semiconductor circuit 11, which in this example comprises the PLC demodulator 19, is connected to a sensor 17. The sensor 17 can detect measured values ​​in an operating device or an LED module. The operating circuit 10 can transmit a signal via the DC bus by means of the PLC demodulator 19 as a function of an output signal from the sensor 17. For example, the operating circuit can transmit information about a temperature detected with the sensor 17.

In order to transmit information through the operating circuit 10, the integrated

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Semiconductor circuit 11 can be set up to modulate a signal onto the DC supply voltage on the DC bus. The integrated semiconductor circuit 11 can comprise a PLC modulator or be connected to a PLC demodulator 19. The PLC demodulator 19 can be set up to encode information in an AC signal that is modulated onto the DC supply voltage on the DC bus.

While exemplary embodiments have been described with reference to the figures, modifications can be implemented in further exemplary embodiments. For example, an operating circuit can also include other DC / DC converters than a step-down converter.

The operating circuit can, for example, also comprise a step-up converter, an inverse converter or a flyback converter. It is also not absolutely necessary for a DC / DC converter to be provided in the operating circuit. For example, a linear current regulator could also be used.

The control signals that are read out by the PLC demodulator do not necessarily have to be generated by a central unit. For example, the techniques described here can also be used for information transfer between operating devices that are connected to the same DC bus.

Devices, systems and methods according to exemplary embodiments can be used in operating circuits for LEDs, for example in LED converters.

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