Abstract:
A device is provided for controlling an illumination device ( 50 ), including a control circuit ( 110 ) having an input ( 102 ) for coupling to a network voltage conductor ( 30 ) and an output ( 104 ) for coupling to a supply voltage conductor ( 40 ) of the illumination device ( 50 ). The control circuit ( 110 ) is designed to supply a supply voltage and control signals modulated onto the supply voltage to the illumination device ( 50 ) via the output ( 104 ). A button ( 120 ) influences the generation of the control signals. The control circuit ( 110 ) produces an internal supply voltage (Vint) from a voltage which reduces between the input ( 102 ) and the output ( 104 ) of the control circuit. In the non-actuated state, the button ( 120 ) bypasses the input ( 102 ) and the output ( 104 ) of the control circuit ( 110 ).

Description:
FIELD OF THE INVENTION 
     The present invention relates to a device for controlling a lighting device. 
     BACKGROUND 
     It is known to use dimmers for brightness control of a lighting device. In lighting devices operating on the basis of conventional lamps such as incandescent bulbs, brightness regulation can take place in the dimmer via phase gating control or phase chopping control of the supply voltage of the lighting device. In the process, the power of the lighting device is reduced by virtue of a short-term interruption to the supply voltage being effected after or prior to the zero crossing of the supply voltage, with the result that, depending on the duration of the interruption, the power of the lighting device is reduced. 
     Furthermore, it is also known to use control devices in which brightness control takes place via special control signals which are transmitted to the lighting device. Electronic control gear (ECG) provided in the lighting device evaluates these control signals and adjusts the brightness correspondingly. This type of control is suitable in particular for lighting devices which are based on lamps in the form of gas discharge lamps or light-emitting diodes. 
     SUMMARY 
     The object of the invention is to provide a device for controlling a lighting device which is suitable for lighting devices based on non-conventional lamps, has a simple design and can be installed with little complexity. 
     This object is achieved by a device and a method as claimed in the independent claims. The dependent claims define developments of the invention. 
     In accordance with one exemplary embodiment, the device therefore comprises a control circuit having an input for coupling to a system voltage conductor and an output for coupling to a supply voltage conductor of the lighting device. The control circuit is configured to supply a supply voltage and control signals modulated onto the supply voltage to the lighting device via the output. The control circuit is configured to modulate control signals by phase gating control and/or phase chopping control as digitally encoded information items onto the supply voltage of the lighting devices. 
     Furthermore, the device comprises a switch, with it being possible for the generation of the control signals to be influenced by the actuation of said switch. For example, by actuating the switch, control signals can be generated which effect brightness control of the lighting device. However, other control operations are also possible, for example color control. The device can comprise one or more further operating elements, such as a potentiometer, for example. The potentiometer can be coupled to a swivel head, for example, through which the desired brightness can be adjusted. 
     The control circuit is configured to generate an internal supply voltage from a voltage which is in the form of a voltage drop between the input and the output of the control circuit. In a non-actuated state, the button bypasses the input and the output of the control circuit. 
     This means that a voltage supply to the control circuit only takes place on actuation of the switch, with the result that the amount of power drawn by the entire arrangement is reduced. Furthermore, no special lines for voltage supply to the control circuit are required, with the result that the installation complexity is reduced. Furthermore, the device is suitable for so-called one-wire wiring, in which the device is connected to a system voltage source via only one conductor and is furthermore connected to the lighting device via only one conductor. If this conductor for coupling to the system voltage source is a phase conductor, for example, a connection to the neutral conductor of the system voltage source is not required in order to ensure the supply of power to the control circuit. However, it goes without saying that the device is not restricted to use with a phase conductor or a neutral conductor. 
     In accordance with an exemplary embodiment, the control circuit comprises a semiconductor component and is configured such that, on actuation of the switch, an operating current of the lighting device flows via the semiconductor component. In this case, the control circuit is in particular configured to derive the internal supply voltage from a voltage drop across the semiconductor component. The semiconductor component can comprise a transistor as controllable switch. Owing to a nonlinear characteristic of the semiconductor component, in this case the internal supply voltage can be derived in an advantageous manner and in particular has a low dependency on the value of the operating current if said operating current exceeds a threshold current in the nonlinear characteristic of the semiconductor component. 
     If the semiconductor component comprises a thyristor, the control circuit can further be configured to modulate the control signals by actuation of the thyristor onto the supply voltage of the lighting device. In this way, a particularly simple design of the control circuit results. 
     In one exemplary embodiment, the control circuit can furthermore comprise a capacitor, which is coupled in parallel with the semiconductor component in order to be charged by the voltage drop across the semiconductor component. In this way, a variation in the voltage drop across the semiconductor component over time can be taken into consideration and the energy stored in the capacitor can be used for operation of DC components of the control circuit. 
     In one exemplary embodiment, the modulation circuit can also have a controllable switch such as a transistor, for example, and can be configured such that an operating current of the lighting device flows via the controllable switch. In this case, the control circuit can be configured to modulate the control signals by actuation of the controllable switch onto the supply voltage of the lighting device as well. The use of a controllable switch enables flexible generation of the control signals and can be used, for example, in combination with a controller for digitally encoding the control signals. In some exemplary embodiments, the control circuit therefore comprises a controller fed by the internal supply voltage. However, it goes without saying here that the controller could also be used for actuating a thyristor. 
     In accordance with one exemplary embodiment, the control circuit is configured to modulate the control signals by phase gating control and/or phase chopping control onto the supply voltage of the lighting device. In this case, predetermined phase gating control or phase chopping control can be used, as the control signals can be encoded by virtue of the presence or absence of said phase gating or phase chopping control. The degree of phase gating control therefore does not need to be varied and is preferably selected to be constant during a small proportion of the period of the supply voltage of the lighting device, with the result that distortion of the supply voltage by the control signals is as low as possible. In accordance with one exemplary embodiment, the phase gating control or the phase chopping control is less than 20% of the period of the supply voltage of the lighting device. 
     For example, the phase gating control or phase chopping control is 10-15% of the period of the supply voltage of the lighting device, with the result that, firstly, reliable detection of the control signals in the lighting device and secondly, low distortion of the supply voltage are ensured. 
     The use of a controllable switch such as a transistor, for example, provides the advantage that different types of signal forms are possible, for example phase gating control or phase chopping control. In contrast to the use of a thyristor, in addition there is not the problem of a holding current, as a result of which even low loads can be actuated without any problems without the need for a base load. 
     Furthermore, in one exemplary embodiment, the phase gating control or phase chopping control can only take place in one half-cycle of the supply voltage. This firstly provides the advantage that the control circuit can be realized with little complexity in terms of circuitry and furthermore limits in an advantageous manner the distortion of the supply voltage by the control signals. 
     The control signals can be used for brightness control of the lighting device, i.e. for dimming the light generated by means of the lighting device. Additionally/alternatively, the control signals can also be used for other control operations, for example for color control of the lighting device, which is of interest for lighting devices with lamps on the basis of light-emitting diodes. 
     It goes without saying that the device can be used with one or more lighting devices which are configured for processing control signals. For this purpose, at least one corresponding lighting device is coupled to the device via the supply voltage conductor, with the result that it can be controlled by the control signals. The processing of the control signals in the lighting device can take place, for example, via ECG. 
     The invention also relates to a method for controlling a lighting device, wherein a control circuit is configured to supply a supply voltage for the lighting device and control signals modulated onto the supply voltage to the lighting device, and 
     wherein the control circuit modulates the control signals by phase gating control and/or phase chopping control as digitally encoded information items onto the supply voltage of the lighting devices. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features, advantages and functions of exemplary embodiments of the invention will become clear from the detailed description below with reference to the attached drawings. 
         FIG. 1  shows a system comprising a device in accordance with an exemplary embodiment of the invention and lighting devices controlled by the device. 
         FIG. 2  shows, schematically, an implementation of the device in accordance with an exemplary embodiment of the invention. 
         FIG. 3  illustrates the mode of operation of the device on the basis of simulation results. 
         FIG. 4  illustrates, by way of example, control signals which can be evaluated in ECG in accordance with an exemplary embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  illustrates a system comprising a device  100  in accordance with an exemplary embodiment of the invention. The system comprises, in addition to the device  100 , a system voltage source  10  and lighting devices  50 . The lighting devices  50  are controlled by the device  100 . In the explanations below, it should be assumed that the device  100  is used for brightness control of the lighting devices  50 , i.e. is in the form of a dimmer. However, it goes without saying that the device  100  could also be used for other or additional control operations, for example for color control of the lighting devices  50 . 
     The lighting devices  50  each comprise ECG  52  and lamps  54 , which are illustrated as light-emitting diodes in the present example. It goes without saying here that the lamps  54  could be implemented in a variety of ways, for example by one or more light-emitting diodes, by one or more gas discharge lamps or else by one or more conventional incandescent bulbs. Furthermore, any desired combination of the mentioned types of lamps can also be used. A suitable operation of the respective lamp  54  takes place via the ECG  52 . For this purpose, the ECG  52  can comprise, for example, a suitable switched mode power supply, which generates supply signals suitable for operation of the lamp  54  from a supply voltage supplied to the lighting device. 
     It goes without saying that the number of lighting devices  50  illustrated in  FIG. 1  is merely by way of example and the system could also be implemented with only one lighting device  50  or with any desired larger number of lighting devices  50 . 
     A system voltage conductor  20  starting from the system voltage source  10  is connected to the lighting devices  50 . A further system voltage conductor  30  starting from the system voltage source  10  is connected to the device  100 . It should be assumed below that the system voltage conductor  20  is a neutral conductor while the system voltage conductor  30  is a phase conductor. However, it goes without saying that other configurations for the system voltage conductor  20  and the system voltage conductor  30  are also possible and can be selected corresponding to the type of connection of the lighting device  50 . The device  100  is in turn connected to the lighting devices  50  via a supply voltage conductor  40 . The lighting devices  50  are coupled in parallel between the system voltage conductor  20  and the supply voltage conductor  40  and draw their supply voltage via the supply voltage conductor  40  and the system voltage conductor  20 . The supply voltage for the lighting devices is thus supplied to said lighting devices firstly, via the system voltage conductor  20  and secondly, via the system voltage conductor  30 , the supply voltage conductor  40  and the device  100  coupled therebetween. Since the device  100  is only directly connected to one of the system voltage conductors  20 ,  30 , the design illustrated in  FIG. 1  corresponds to a so-called one-wire interconnection. A connection of the device  100  to the system voltage line  20  is not necessary, which reduces installation complexity. 
     The device  100  comprises a control circuit  110  and, for example, a button  120 . The control circuit  110  has the task of modulating control signals onto the supply voltage of the lighting devices  50 . The device  100  can comprise one or more further operating elements, which is illustrated in the example in  FIG. 1  by a potentiometer  130 . The potentiometer  130  can be coupled, for example, to a swivel head, via which the desired brightness can be adjusted. In this case, the device  100  can detect the position of the potentiometer  130  on actuation of a button  120  and generate control signals for adjusting the corresponding brightness via the control circuit  110  and transmit said control signals to the lighting devices  50 . By a combination of various operating elements with the button  120 , a wide variety of control operations can be realized. 
     For example, brightness control could take place via the potentiometer  130 , whereas color control could take place via the button  120 . The control signals are preferably transmitted as digitally encoded information items. 
     The generation of the control signals can also be capable of being influenced by actuation of the button  120 . For example, on actuation of the button  120 , control signals can be generated which instruct the lighting devices  50  to implement a brightness change. For example, by actuation of the switch, the brightness can be increased by in each case one increment until a maximum brightness is reached, and then, by actuation of the button  120 , the brightness can again be reduced by in each case one increment until a minimum brightness is reached. Furthermore, in the case of permanent actuation of the switch, the brightness could be changed automatically periodically and the brightness set when the button  120  is released could be maintained. It goes without saying that, furthermore, a wide variety of other possibilities for controlling the lighting devices  50  via the button  120  are provided. 
       FIG. 2  illustrates, schematically, an implementation of the control circuit  110  in the device  100  shown in  FIG. 1 .  FIG. 2  illustrates, by way of example, only one lighting device  50 , which has a load resistor RL. However, it goes without saying that, as mentioned above, further lighting devices could also be provided. Furthermore,  FIG. 2  also illustrates a mains switch  140 , which may be a further operating element of the device  100  or a switch which is provided separately from the device  100 . 
     As illustrated in  FIG. 2 , the control circuit  110  comprises an input  102 , which is used for connection to the system voltage line  30 , and an output  140 , which is used for connection to the supply voltage line  40 . The button  120  is coupled between the input  102  and the output  104 , with the result that, on actuation of the button  120 , the input  102  and the output  104  are electrically bypassed. The mains switch  140  is coupled between the system voltage source  10  and the input  102 . 
     The control circuit  110  is configured to effect the modulation of the supply voltage with the control signals by means of a transistor M 1 . The transistor M 1  is coupled between the input  102  and the output  104  of the control circuit  110  in such a way that an operating current of the lighting device  50  flows through the transistor M 1 . By actuation of the transistor M 1 , the supply voltage can consequently be modulated with the control signals. 
     In the example illustrated, the transistor M 1  is a field-effect transistor, in a particular a field-effect transistor of the MOSFET type. However, it goes without saying that other types of transistor could also be used. 
     Furthermore, the control circuit  110  for generating the control signals comprises a controller  150 , a DC-to-DC converter  160  and an amplifier circuit comprising resistors R 1 , R 2 , R 3 , R 4  and a transistor Q 1 , which are coupled in the manner illustrated in  FIG. 2  between an output of the controller  150  and a control terminal of the transistor M 1 . The amplifier circuit serves to amplify output signals from the controller  150  to a signal level suitable for actuating the transistor M 1 . The DC-to-DC converter  160  produces a voltage required for the operation of the amplifier circuit, for example a DC voltage of 12-15 volts. The DC-to-DC converter  160  can be implemented, for example, on the basis of a charge pump. However, it goes without saying that in some exemplary embodiments, the output signal of the controller  150  itself could also already be suitable for actuating the transistor M 1 , with the result that it would be possible to dispense with the amplifier circuit and the DC-to-DC converter  160 . 
     In the exemplary embodiment illustrated, the transistor Q 1  is a bipolar transistor, for example an npn transistor. The resistors R 1 , R 2 , R 3  and F 4  are dimensioned suitably corresponding to the signal levels used. 
     Furthermore, the control circuit  110  in the exemplary embodiment illustrated in  FIG. 2  comprises a supply circuit  180 , which generates an internal supply voltage Vint of the control circuit  110  from a voltage which is in the form of a voltage drop between the input  102  and the output  104  of the control circuit  110 . This internal supply voltage Vint is used for operating the controller  150 , the DC-to-DC converter  160  and the amplifier circuit. 
     As illustrated, the supply circuit  180  comprises a diode D 1 , a further diode D 2  and a capacitor C 1 . The diode D 2  is a Zener diode. The diode D 2  is coupled in series with the transistor M 1 , with the result that the operating current of the lighting device  50  flows through the diode D 1  when the button  120  is actuated. The capacitor C 1  is coupled to the diode D 1  in parallel with the diode D 2 , with the result that the capacitor C 1  is charged by a voltage drop across the diode D 2 , which takes place, owing to the diode D 1 , during the negative half-cycle of the supply voltage. The diode D 1  can be a silicon diode. 
     The variations in the voltage drop across the diode D 2  over time are averaged out by means of the capacitor C 1  and energy storage takes place, with the result that the internal supply voltage Vint generated by the supply circuit  180  substantially corresponds to a DC voltage. The capacitor C 1  can be dimensioned, for example, in the region of a few μF. In the exemplary embodiment illustrated in  FIG. 2 , a DC voltage reference point P 0  is formed at a terminal of the capacitor C 1 , which terminal is connected to the input  102  of the control circuit  110 . 
     Furthermore, the control circuit  110  in the exemplary embodiment illustrated in  FIG. 2  comprises a further diode D 3 , which is connected in parallel with the transistor M 1 , as illustrated in  FIG. 2 . The diode D 3  can be a silicon diode. 
     If, in the exemplary embodiment illustrated in  FIG. 2 , the mains switch  140  is closed, in the non-actuated state of the button  120  the system voltage provided by the system voltage source  10  is present directly as supply voltage at the lighting device  50 . This is due to the fact that, in the non-actuated state of the button  120 , said button electrically bypasses the input  102  and the output  104  of the control circuit  110 , with the result that the control circuit  110  does not have any energy supplied to it. In this way, the control circuit  110  is prevented from drawing power in the non-actuated state of the button  120 . 
     In the actuated state of the button  120 , i.e. when the button is pressed, however, the electrical bypassing of the input  102  and the output  104  of the control circuit  110  is interrupted, with the result that the operating current of the lighting device  50  flows via the input  102  and the output  104  of the control circuit  110  through the control circuit  110 . In particular, the operating current flows through the diode D 2 , the transistor M 1  and the diode D 3 , which is connected in parallel with the transistor M 1 . 
     In this state, the capacitor C 1  is charged by the voltage drop across the diode D 2  and stores energy for generating the internal supply voltage Vint. This takes place due to the polarities of the diodes D 1  and D 2  illustrated in  FIG. 2  during the negative half-cycle. Owing to the internal supply voltage Vint, the controller  150  and the DC-to-DC converter  160  are supplied with energy, with the result that the control signals are modulated onto the supply voltage corresponding to the programming of the controller  150 . 
     For example, the controller  150  can detect the position of a potentiometer, for example of the potentiometer  130  in  FIG. 1 , and generate the control signals corresponding to the established position of the potentiometer and preferably transmit these control signals as digitally encoded information items. However, it is also possible for only the information “button pressed” to be transmitted to the lighting device  50  via the control signals. 
       FIG. 3  illustrates, on the basis of simulation results, the way in which the control circuit  110  illustrated in  FIG. 3  functions. The graph at the top in  FIG. 3  illustrates, by means of a continuous line, the voltage used for actuating the transistor M 1 , whereas a dashed line illustrates the profile of the internal supply voltage Vint. The diagram at the bottom illustrates the profile of the supply voltage supplied to the lighting device  50 . During the simulation, it has been assumed that, at time t 1 =45 ms, the button  120  is pressed and, at time t 2 =160 ms, the button  120  is released again. 
     As can be seen in  FIG. 3 , after actuation of the button at time t 1 , the internal supply voltage Vint increases and, after a few periods of the supply voltage, reaches a substantially constant value. At the time of the positive zero crossing of the supply voltage, an interruption to the actuation of the transistor M 1  then takes place, with the result that the transistor M 1  turns off for a predetermined period. As a result, the supply voltage remains substantially at zero for this period during its positive zero crossing and the phase gating control illustrated in  FIG. 3  of the positive half-cycle takes place. Care should be taken here to ensure that the predetermined period for which the actuation of the transistor M 1  is interrupted is determined via the controller  150  and the magnitude of the resulting phase gating control is determined. In the example illustrated, a predetermined period of 2 ms has been selected, which, assuming a system frequency of 50 Hz, corresponds to phase gating control of 10% of the period of the system voltage. By virtue of the presence or absence of phase gating control in the supply voltage, the control signals are encoded. In this case, it goes without saying that the controller  150  can also have the effect, when the button  120  is pressed, that in certain half-cycles no phase gating control occurs. In this way, digital encoded information items can be transmitted via the control signal. For example, the presence of the phase gating control can encode a digital value “1”, whereas the absence of phase gating control can encode a digital value “0”. 
     In modified exemplary embodiments, the control signals can also be encoded in a different way, for example by phase chopping control, i.e. by actuation of the transistor M 1  prior to a negative zero crossing of the supply voltage, or by actuation of the transistor M 1  at other points in time. The actuation of the transistor M 1  at the time of a zero crossing of the supply voltage is considered to be advantageous, however, since in this case only switch-on losses occur in the transistor M 1 . In the implementation illustrated, the first half-cycle of the supply voltage is used for generating the internal supply voltage Vint. However, it is also possible to use the second half-cycle or both half-cycles. In this case, the capacitor C 1 , the transistor M 1  could be provided as controllable switch and the diodes D 1  and D 2  could alternatively or additionally be provided with reverse polarity. Furthermore, warm-up resistance could also be used from the drain terminal of the transistor M 1  to the circuit node between the capacitor C 1  and the diode D 1 . 
     As an alternative implementation of the control circuit  110 , a thyristor can also be coupled between the input  102  and the output  104  of the control circuit  110 , with the result that, when the button  120  is pressed, the operating current of the lighting device  50  flows through the thyristor. A diode can be coupled in parallel with the thyristor X 1 . Such an exemplary implementation of the control circuit  110 , in comparison with the implementation shown in  FIG. 2 , provides a simplified design and can in particular dispense with the controller  150  and the DC-to-DC converter  160 . Instead of this, a trigger circuit can be provided, via which the magnitude of a fixedly predetermined phase gating control is defined. In the case of such an implementation, as has been mentioned, a thyristor can be provided instead of the transistor M 1 . Other variant implementations of the trigger circuit can likewise be used. For example, the trigger circuit could also be implemented by means of a DIAC. 
     Therefore, control signals can be modulated in a similar way by phase gating control onto the supply voltage by means of an implementation of the control circuit  110  with a thyristor, as is illustrated in the diagram at the bottom in  FIG. 3 . In comparison to the implementation shown in  FIG. 2 , however, the control signals can merely also be used to indicate whether the button  120  has been actuated or not. In particular, the presence of the phase gating control can indicate an actuated state of the button  120 . 
     In comparison with the implementation shown in  FIG. 2 , to this extent a simplified circuit design results in that the controller  150  and the DC-to-DC converter  160  can be dispensed with. Furthermore, the generation of the internal supply voltage Vint can also be simplified since no separate zener diode needs to be provided, but instead the voltage drop across the thyristor is used to generate the internal supply voltage Vint, wherein the thyristor is at the same time used for modulation of the supply voltage. 
     In one exemplary embodiment, the lighting device  50  can be compatible both with the implementation of the control circuit  110  shown in  FIG. 2  and with the implementation of a control circuit  110  with a thyristor. This can be achieved by virtue of the fact that, when using a more complex digital encoding of the control signals, this is indicated by a special start sequence. For example, the controller  150  in the implementation shown in  FIG. 2  could, on actuation of the switch, first generate in a predetermined half-cycle with phase gating control, with the result that, for example, a sequence of digital values “1101” is generated, which indicates that a more complex digital encoding follows. The simplified implementation with a trigger circuit, on the other hand, would generate a sequence corresponding to the digital values “1111” on actuation of the button  120 , with the result that the lighting device can decide between the two implementations. Thus, the compatibility of the device can be increased by virtue of the controller  150  first generating a special start sequence on actuation of the button  120 . 
     An example of control signals used for transmitting digital information items is illustrated in  FIG. 4 . In  FIG. 4 , the time t 1  in turn corresponds to the depression of the button  120  and the time t 2  corresponds to the release of the button  120 . It can be seen that the output signal A 2  demonstrates pulses, while the button  120  is depressed. As explained in connection with  FIG. 2 , the modulation of the supply voltage can take place with the control signals only in certain half-cycles, with the result that information items can be digitally encoded in the control signals. This can be effected in the device  100  by means of a controller, for example the controller  150 . 
     The control signals illustrated by way of example in  FIG. 4  are divided into different sequences S 1 , S 2 , S 3  and S 4 . The sequence S 1  is a start sequence, by means of which the use of a more complex digital encoding can be indicated to the ECG  52 . The start sequence can contain, for example, a “0” at a predetermined position. 
     By means of the start sequence, the ECG  52  can decide whether a control circuit with a controller is used in the device  100 , such as in the implementation shown in  FIG. 2 , for example, or a simplified control circuit, as in the implementation with a trigger circuit, which is not capable of inserting, in a targeted manner, a “0” into the sequence in the control signals. For example, the sequence “1101” can be used as start sequence. In sequence S 2 , which can have a length of 8 bits, for example, digital information items can be encoded, for example a control command or the like. By means of the information items encoded in the sequence S 2 , it is also possible to indicate to the ECG  52  the way in which transmitted control signals will subsequently be used. 
     The sequence S 3  can be a stop sequence, by means of which the end of the digital encoded information items is indicated. 
     The sequence S 4  can in turn be a sequence of pulses for incrementally increasing or decreasing the brightness of the lighting device  50 , i.e. each pulse in the sequence S 4  can correspond, for example, to the increase or decrease in the brightness by one increment. 
     By virtue of digitally encoded information items being transmitted via the control signals, a wide variety of control functions can be realized in a simple manner in the ECG  52 . For example, it could be possible to indicate to the ECG  52  by means of the information items encoded in the sequence S 2  that the pulses in the sequence S 4  are intended to be used for adjusting the brightness for a so-called corridor function. In the case of the corridor function, the lighting device  50  can be activated, for example, by a motion sensor and then dimmed to a predetermined brightness value once a predetermined time span has elapsed. This predetermined brightness value could be transmitted to the ECG  52  after corresponding indication in the information items of the sequence S 2  via the sequence S 4 . 
     It goes without saying that, in order to implement this and other more complex control functionalities, the device  100  for generating the control signals can be equipped with corresponding operating elements. 
     The preceding concepts for controlling a lighting device therefore provide a low level of installation complexity. For example, existing dimmers which use “one-wire” circuitry can be replaced by the device according to the invention without additional lines needing to be laid. 
     Furthermore, the concepts for a wide variety of types of lighting devices on the basis of a wide variety of lamps are suitable. The device according to the invention, owing to its low degree of complexity, takes up only a small amount of space and can be arranged, for example, in a switch box. Finally, by virtue of the fact that distortion in the supply voltage of the lighting device is largely avoided, the requirements placed on the ECG of the lighting device are also less stringent. For example, base load reproduction can be dispensed with. 
     It goes without saying that, in the exemplary embodiments described in the text above, a wide variety of modifications are possible without departing from the scope of the invention. For example, individual circuit components can be replaced by similar components with comparable function. Furthermore, features of the individual implementations can also be combined with one another in a suitable manner. Thus, for example, the controller described with reference to  FIG. 2  could also be used for actuating a thyristor. Furthermore, the control signals can also be modulated by phase gating control or phase chopping control of both half-cycles onto the supply voltage, which can be achieved, for example, by correspondingly doubling up on parts of the control circuit, possibly with reverse polarity of diodes or the like. By virtue of independent modulation of the positive and negative half-cycle with control signals, different information items can be transmitted simultaneously. For example, by virtue of modulation of a half-cycle, a brightness value can be transmitted, while, by modulation of the other half cycle a color value or the like is transmitted. However, it goes without saying that, by virtue of independent use of both half-cycles, a wide variety of other possibilities for transmission of different information items results. Finally, it goes without saying that the implementation of the control circuit  110  illustrated in  FIG. 2  can be implemented by suitable circuitry of discrete components on a printed circuit board or can be integrated at least partially in a single semiconductor module.