Method and circuit with driver module for light-emitting diodes

Abstract

Procedure, comprehensive: Sequential coupling, by means of a switching module (110, 310, 510, 610, 710, 810) of a circuit (100, 300, 500, 600, 700, 800), of each cell of several cells (112, 312, 512, 612, 712, 812) to a driver module (110, 206, 306, 506, 606, 706, 806), wherein each cell of the several cells (112, 312, 512, 612, 712, 812) comprises a light-emitting diode (338, 538, 638, 738, 838) configured to be activated based on a control voltage at a respective cell; and Drive, by the driver module (110, 206, 306, 506, 606, 706, 806), the control voltage of a respective cell of the multiple cells (112, 312, 512, 612, 712, 812) based on a reference current, when the switching module (110, 310, 510, 610, 710, 810) sequentially couples a respective cell of the multiple cells (112, 312, 512, 612, 712, 812) to the driver module (110, 206, 306, 506, 606, 706, 806), wherein the driver module (110, 206, 306, 506, 606, 706, 806) comprises an operational amplifier (340, 540, 640, 740, 840), wherein the operational amplifier (340, 540, 640, 740, 840) has an output (350, 550, 650, 750), a first input (352, 552, 652, 752) and a second input (354, 554, 654, 752), and wherein the sequential coupling of each cell of the multiple cells (112, 312, 512, 612, 712, 812) to the driver module (110, 206, 306, 506, 606, 706, 806) The following includes: Coupling the output (350, 550, 650, 750), the first input (352, 552, 652, 752) and the second input (354, 554, 654, 752) to a respective cell of the multiple cells (112, 312, 512, 612, 712, 812) during the program state of the circuit (100, 300, 500, 600, 700, 800); and decoupling the operational amplifier (340, 540, 640, 740, 840) from each cell of the multiple cells (112, 312, 512, 612, 712, 812) and coupling the first input (352, 552, 652, 752) to the second input (354, 554, 654, 752) during a switching state of the circuit (100, 300, 500, 600, 700, 800).

Description

Technical field

[0001] The present disclosure relates to light-emitting components and in particular to techniques and circuits associated with light-emitting diodes (LEDs), especially methods and circuits with a driver module for light-emitting diodes. background

[0002] Light-emitting components, such as light-emitting diodes (LEDs), can be operated by a driver circuit. The driver circuit can control the light output of an LED by varying the average current flowing through it. For example, the driver circuit can increase the duty cycle of the current supplied to an LED to increase the light output. Conversely, the driver circuit can decrease the duty cycle of the current supplied to an LED to decrease the light output.

[0003] US patent 2010 / 0073265A1 discloses a sequential programming of LED cells using an adjustable programming voltage.

[0004] DE 10 2016 109 296 A1 and DE 11 2017 000 341 T5 disclose devices for controlling multiple light sources, in particular light-emitting diodes, arranged in a matrix structure. Brief description

[0005] A method according to claim 1 and a circuit according to claim 7 are provided. The dependent claims define further embodiments. The disclosure describes techniques, components, and systems for driving light-emitting devices. In some examples, a single driver module of a circuit can program multiple light-emitting diodes (LEDs) or a set of LEDs (e.g., in an LED matrix device). For example, a driver module can program a first LED for a desired duty cycle and a desired LED current. In this example, after programming the first LED, a switching module can decouple the first LED from the driver module and couple the driver module to a second LED. After the driver module is coupled to the second LED, the driver module can program the second LED for a desired duty cycle and a desired LED current.

[0006] In one example, a method involves sequentially coupling each cell of a multi-cell array to a driver module via a switching module of a circuit. Each cell contains an LED configured to activate based on a control voltage applied to that cell. The method further involves the driver module applying the control voltage to each cell based on a reference current when the switching module sequentially couples each cell to the driver module.

[0007] In another example, a circuit contains a driver module and a switching module. The driver module is configured to receive a reference current for multiple cells. Each cell of the multiple cells contains an LED configured to activate based on a control voltage applied to that specific cell. The switching module is configured to sequentially connect each cell of the multiple cells to the driver module. Furthermore, the driver module is configured to drive a control voltage to each cell of the multiple cells based on the reference current when the switching module sequentially connects that cell to the driver module.

[0008] In the method and circuit, the driver module comprises an operational amplifier, wherein the operational amplifier has an output, a first input and a second input, and wherein the sequential coupling of each cell of the multiple cells to the driver module comprises the following: Coupling the output, first input, and second input to a respective cell of the multiple cells during the program state of the circuit; and decoupling the operational amplifier from each cell of the multiple cells and coupling the first input to the second input during a switching state of the circuit.

[0009] Details of these and other examples are set forth in the accompanying drawings and the following description. Other features, functions, and advantages will become apparent from the description, the drawings, and the claims. Brief description of the drawings Fig. Figure 1 is a block diagram representing an example system configured for mass LED cell programming according to one or more techniques of this disclosure. Fig. Figure 2 is a block diagram representing an example LED matrix device according to one or more techniques of this disclosure. Fig. Figure 3 is a circuit diagram that represents a first example circuit for mass LED cell programming according to one or more techniques of this disclosure. Fig. Figure 4 is a representation of an example switching signal for sequential switching according to one or more techniques of this disclosure. Fig. 5 is a representation of a first programming state according to one or more techniques of this disclosure. Fig. Figure 6 is a representation of a switching state according to one or more techniques of this disclosure. Fig. 7 is a representation of a second programming state according to one or more techniques of this disclosure. Fig. Figure 8 is a circuit diagram that represents a second example circuit for mass LED cell programming according to one or more techniques of this disclosure. Fig. Figure 9 is a flowchart for the mass LED cell programming that can be performed by a circuit according to this disclosure. Fig. Figure 10 is a representation of an example programming time for a switching signal for mass LED cell programming according to one or more techniques of this disclosure. Detailed description

[0010] In general, this disclosure concerns techniques for enabling mass light-emitting diode (LED) cell programming. In some systems, each driver circuit can program an individual LED for a desired duty cycle and LED current. For example, each LED cell of an LED matrix device may contain a driver circuit for programming only that specific LED cell of the LED matrix device. However, the number of connections for operating the LED matrix device can increase with the number of LED cells in the LED matrix device. As such, LED matrix devices with a large number of LED cells (e.g., 1024 LED cells or more) may have a complex routing structure for the connections required to operate the LED matrix device.

[0011] According to embodiments described herein, a switching module can couple a driver module to multiple LED cells, enabling a single driver module to program several LED cells. For example, after the switching module couples the driver module to a first LED cell arranged in a column of LED cells in an LED matrix device, the driver module can program the first LED cell. While programming the first LED cell, the switching module can couple the driver module to a second LED cell arranged in the same column. After the switching module couples the driver module to the second LED cell, the driver module can program the second LED cell. In this way, fewer components may be used to drive multiple LED cells. Furthermore, in some cases, such LED matrix devices can contain over 1000 LED cells (e.g., 1024) arranged for high pixel density.As such, one or more of the techniques described herein can allow LED matrix devices to have a higher pixel density than LED matrix devices that contain a driver for programming only one LED cell.

[0012] Fig. Figure 1 is a block diagram representing an example system 100 configured for mass LED cell programming according to one or more techniques of this disclosure. Although Fig. Figure 1 shows that the system 100 has separate and distinct components, such as a voltage source 102, a control module 104, a driver module 106, and an LED matrix component 108. Two or more components can be combined. For example, the driver module 106 and the LED matrix component 108 can be two individual components, or they can represent a combination of one or more components that provide the functionality of the system 100 as described herein.

[0013] The voltage source 102 can be configured to supply electrical power to one or more other components of the switching system 100. For example, the voltage source 102 can be configured to supply electrical power to LED cells 112. In some examples, the voltage source 102 can be an output to one or more battery cells. Examples of battery cells can include lead-acid, nickel-metal hydride, lithium-ion, or other types of battery cells. In some examples, the voltage source 102 can be an output of a power converter, such as a rectifier. For example, the voltage source 102 can be a rectified AC output. Examples of rectifiers can include, but are not limited to, single-phase rectifiers (e.g., half-wave, full-wave, or the like), three-phase rectifiers (e.g., half-wave, full-wave, bridge, or the like), or other types of rectifiers.In some examples, the voltage source 102 can represent a connection to an electrical network. For example, the voltage source 102 can be a rectified output of an AC-DC power converter, which provides a V. AC receives power from an electrical network (e.g. 120 V) AC at 60 Hz, 230 V AC at 50 Hz or another output from an electrical network).

[0014] The LED matrix component 108 can contain any component capable of holding two or more LEDs. As shown, the LED matrix component 108 can contain switching modules 110A-110N (collective switching modules 110 or switching module 110) and LED cells 112A-112N (collective LED cells 112). Although the example of Fig. 1. If the LED matrix component 108 is represented as containing a column of LED cells 112, one or more of the techniques described herein can be used with an LED matrix component 108 containing multiple columns of LED cells. For example, the LED matrix component 108 can contain 64 columns of LED cells, with each column containing 64 LED cells. In examples where the LED matrix component 108 contains multiple columns of LED cells, each column of LED cells of the LED matrix component 108 can be substantially equivalent to the LED cells 112.

[0015] The LED cells 112 can refer to two or more suitable semiconductor light sources. For example, each LED cell 112 can contain one LED. In some examples, each LED cell 112 contains a pn junction configured to emit light when activated. Each LED cell 112 can contain an LED configured to activate based on a control voltage. For example, an LED contained in LED cell 112A can activate when a control voltage across LED cell 112A exceeds a threshold. In some examples, a parasitic capacitance and / or a capacitor can store the control voltage.

[0016] The control module 104 can be configured to generate a switching signal to actuate the switching modules 110. In some examples, the control module 104 can contain an analog circuit. In other examples, the control module 104 can be a microcontroller on a single integrated circuit containing a processor core, memory, inputs, and outputs. For example, the control module 104 can contain one or more processors, including one or more microprocessors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or any other equivalent integrated or discrete logic circuit arrangement, as well as any combination of such components.The term "processor" or "processing circuit arrangement" can generally refer to any of the above logic circuit arrangements alone or in combination with another logic circuit arrangement, or to any other equivalent circuit arrangement. In some examples, the control module 104 can be a combination of one or more analog components and one or more digital components.

[0017] The switching modules 110 can refer to two or more suitable switching elements. In some examples, each switching module of the switching modules 110 can contain one or more circuit elements. Examples of switching elements include a silicon-controlled rectifier (SCR), a field-effect transistor (FET), and a bipolar junction transistor (BJT). Examples of FETs include a junction field-effect transistor (JFET), a metal-oxide-semiconductor FET (MOSFET), a dual-gate MOSFET, an insulated-gate bipolar transistor (IGBT), any other type of FET, or any combination thereof. Examples of MOSFETs include a PMOS, an NMOS, a DMOS, or any other type of MOSFET, or any combination thereof.Examples of BJTs include PNP, NPN, heterojunction, or any other type of BJT, or any combination thereof. It is understood that switching elements can include a high-side switch or a low-side switch. Furthermore, switching elements can be voltage-controlled and / or current-controlled. Examples of current-controlled switching elements include gallium nitride (GaN) MOSFETs, BJTs, or other current-controlled devices.

[0018] The driver module 106 can be configured to drive a control voltage to LED cells 112. For example, the driver module 106 can contain an operational amplifier that drives the control voltage such that a voltage received at a first input of the operational amplifier is equal to a voltage received at a second input of the operational amplifier. For example, the driver module 106 can "program" a control voltage. For example, at the beginning edge of an "on" section of a duty cycle, the driver module 106 can drive a control voltage to LED cell 112A to activate an LED in LED cell 112A. After the driver module 106 drives the control voltage to activate the LED, a capacitor (e.g., a parasitic capacitor, a capacitor bank, etc.) holds the control voltage to keep the LED in LED cell 112A illuminated during the "on" section of the duty cycle.Then, at the end edge of the "on" section of the duty cycle, the driver module 106 can drive the control voltage to LED cell 112A to deactivate an LED in LED cell 112A. After the driver module 106 drives the control voltage to deactivate the LED, the capacitor (e.g., parasitic capacitor, capacitor unit, etc.) maintains the control voltage to deactivate the LED in LED cell 112A during the "off" section of the duty cycle.

[0019] The driver module 106 can optionally include a current source. For example, the driver module 106 can include a current source that generates a reference current. The driver module 106 can control a control voltage based on this reference current. For example, the driver module 106 can drive the control voltage at the LED cell 112A such that the current at the LED cell 112A corresponds to the reference current when the switching module 110A couples the driver module 106 to the LED cell 112A.

[0020] In operation, the driver module 106 receives a reference current for LED cells 112. For example, the driver module 106 receives a reference current generated by a current source. Each LED cell of the LED cells 112 contains an LED configured to activate based on a control voltage applied to that specific LED cell. The switching modules 110 are configured to sequentially couple each LED cell of the LED cells 112 to the driver module 106. The driver module 106 is further configured to drive a control voltage to each LED cell of the LED cells 112 based on the reference current when the switching modules 110 sequentially couple each cell of the LED cells 112 to the driver module 106.

[0021] In Fig. Figure 2 is a block diagram representing an example LED matrix device 208 according to one or more techniques of this disclosure. As shown, the system 200 may contain an LED matrix device 208 containing columns 209A-209E (collectively, columns 209). Although Fig. Since Figure 2 represents four rows and five columns of LED cells, it is understood that an LED matrix component can contain different quantities of rows and / or columns. For example, the LED matrix component can contain 32 rows and 32 columns, 32 rows and 64 columns, 64 rows and 32 columns, 64 rows and 64 columns, or other quantities of rows and / or columns.

[0022] Although Fig. where 1 represents a number "n" of LED cells, the number "n" of LED cells can be represented by Fig. The techniques described in section 1 can be applied to each column of columns 209. For example, each of columns 209 can be configured to work with one of the driver modules 206A-206E (collectively, driver modules 206).

[0023] For example, a switching module not shown can sequentially switch each LED cell of column 209A to the driver module 206A, a switching module not shown can sequentially switch each LED cell of column 209B to the driver module 206B, etc.

[0024] In some examples, each of the columns 209 can be associated with a reference current. For example, each of the columns 209 can be associated with a common reference current. For example, each column 209 can have a reference current of 52 microamperes (µA). In some examples, each of the columns 209 can be associated with a reference current that is different from reference currents assigned to other columns of the columns 209. For example, column 209A can have a reference current of 52 microamperes (µA), and column 209B can have a reference current of 66 microamperes (µA).

[0025] The driver modules 206 can be located outside the LED matrix device 208. For example, the driver modules 206 can be formed on a substrate different from the LED matrix device 208. In some examples, the driver modules 206 and the LED matrix device 208 can be located within a common package. For example, the LED matrix device 208 can be a common package that includes a first substrate with switching modules 110. Fig. 1, a second substrate with 112 LED cells Fig. 1 and a third substrate containing 206 driver modules.

[0026] In systems containing a driver module and a switching module for each LED cell, the number of top metal connections can increase proportionally to the number of LED cells in an LED matrix device. For example, a top metal connection for a column of LEDs in an LED matrix device might contain 8 pins for that column. These could include, for example, a row enable pin, a data enable pin, a reset pin, a gate-for-NMOS current mirror pin, a logic supply pin, a ground pin, a charge pump supply pin, and an LED supply pin. Furthermore, in systems containing a driver module for each LED cell in a column of 64 LED cells, the top metal connection for a column of LEDs in an LED matrix device might still contain 64 reference current pins and 64 output LED pins. Therefore, each column of 64 LED cells could necessarily utilize 138 top metal connections.

[0027] According to one or more of the techniques described herein, the System 200 can be configured for mass LED cell programming. Instead of including a driver module for each LED cell in the LED matrix device 208, the LED matrix device 208, for example, includes a driver module 206 for each column of columns 209. For example, the driver module 206A can program each LED cell in column 209A, the driver module 206B can program each LED cell in column 209B, the driver module 206C can program each LED cell in column 209C, the driver module 206D can program each LED cell in column 209D, and the driver module 206E can program each LED cell in column 209E. As such, the number of upper metal connections for a column of LEDs of the LED matrix device 208 can be significantly smaller than in systems that include a driver module for each LED cell.For example, the top metal connection for column 209A of the LED matrix device 208 can contain 10 pins for the column. These pins could include, for example, a row enable pin, a data enable pin, a reset pin, a gate-for-NMOS current mirror pin, a logic supply pin, a ground pin, a charge pump supply pin, an LED supply pin, a high-side switching element power supply, and a reference current pin for column 209A. Furthermore, in systems that include a driver module for each LED cell in a column of 64 LED cells, the top metal connection for a column of LEDs in an LED matrix device can still contain 64 output LED pins.As such, each column of 64 LED cells can necessarily use 76 top metal connections, which is significantly fewer than the 138 top metal connections that can be used in systems that include a driver module for each LED cell, thus reducing cost and complexity in a resulting component.

[0028] Furthermore, in cases where each driver module contains a charging pump, the LED matrix component 208 can have reduced power consumption compared to systems that have one driver module for each LED cell, because the System 200 uses fewer driver modules. For example, in systems that have one driver module for each LED cell in a column of 128 LED cells, which has 64 rows of LED cells and a current consumption of 6 microamperes (6 µA), the total current might be 50 milliamperes (mA). The System 200, however, can instead have a total current of 3 milliamperes (mA).

[0029] Fig. Figure 3 is a circuit diagram representing a first example circuit 300 for mass LED cell programming according to one or more techniques of this disclosure. As shown, the circuit 300 includes a voltage source 302, a driver module 306, switching modules 310A-310N (collectively switching modules 310 or switching module 310), and LED cells 312A-312N (collectively LED cells 312). The voltage source 302 can be an example of the voltage source 102 of Fig. 1. Driver module 306 can be an example of driver module 106 from Fig. 1. The 312 LED cells can be an example of the 112 LED cells from Fig. 1. The switching modules 310A-310N can be an example of the switching modules 110 from Fig. 1. The switching modules 310 and / or the LED cells 312 may be contained in an LED matrix component not shown.

[0030] The LED cell 312A can contain a switching element 332A, a switching element 334A, a capacitor 336A, and an LED 338A. Although shown as a single package, it is understood that components of the LED cell 312 can be formed on different substrates. For example, the LED 338A can be formed on a substrate different from one containing the switching element 332A, the switching element 334A, and the capacitor 336A. As discussed below, the LED cell 312A is configured to activate the LED 338A based on a control voltage. Although the following discusses the LED cell 312A, it is understood that other LED cells of the LED cell 312 can be substantially similar to the LED cell 312A.For example, the LED cell 312N can contain a switching element 332N, which is similar to the switching element 332A, a switching element 334N, which is similar to the switching element 334A, a capacitor 336N, which is similar to the capacitor 336A, and an LED 338N, which is similar to the LED 338A.

[0031] The switching element 332A can be configured to control a current at the LED 338A to correspond to a control voltage at a gate of the switching element 332A. For example, as the gate voltage at the switching element 332A increases, the current supplied by the voltage source 302 to the LED 338A can increase. Similarly, as the gate voltage at the switching element 332A decreases, the current supplied by the voltage source 302 to the LED 338A can decrease. The switching element 332A can be a transistor. For example, the switching element 332A can be an NMOS transistor. In some cases, the switching element 332A can be a PMOS transistor.

[0032] The switching element 332A can be configured to generate an LED current (“LED A “) at the LED cell 312A. For example, the switching element 332A can generate an LED current output at a source of the switching element 332A when a control voltage at a gate of the switching element 332A increases. Analogously, the switching element 332A can generate the LED current output at the source of the switching element 332A, which decreases with the control voltage at a gate of the switching element 332A.

[0033] The switching element 334A can be configured to generate a sensing current ("SENSE"). A“) at the LED cell 312A. For example, the switching element 334A can generate a sensing current output at a source of the switching element 334A, which increases with a current at the current reference 334. Analogously, the switching element 334A can generate the sensing voltage output at the source of the switching element 334A, which decreases with a current at the current reference 334. The switching element 334A can be a transistor.

[0034] For example, the switching element 334A can be an NMOS transistor. In some cases, the switching element 334A can be a PMOS transistor.

[0035] Switching elements 332A and 334A can be tuned such that a current flowing through one of them can precisely correspond to a current flowing through the other. For example, in response to receiving a specific gate signal, a current flowing through switching element 332A can be forty times greater than a current flowing through switching element 334A. In this way, a current flowing through switching element 334A can be scaled by switching element 332A with a scaling factor of K:1.

[0036] Capacitance 336A can be a parasitic capacitance at a gate of switching element 332A. In some examples, capacitance 336A may include a capacitor. As used here, a capacitor can include any suitable electrical component configured to store electrical energy in an electric field. For example, capacitance 336A may include a capacitor. Examples of a capacitor may include, but are not limited to, ceramic capacitors, film capacitors, electrolytic capacitors (e.g., aluminum, tantalum, niobium, or the like), supercapacitors (e.g., double-layer, pseudocapacitors, hybrid capacitors), mica capacitors, or the like. Although capacitance 336A can be described as a single capacitor, it may also contain an array of capacitive elements.For example, a 336A capacitor can consist of an array of capacitive elements connected in parallel and / or in series. In some cases, each capacitive element can be a discrete component, while in other cases, each capacitive element can be contained within a single package (e.g., a capacitor array).

[0037] The driver module 306 can contain an operational amplifier 340, a switching element 342, a power source 344, and a charging pump 346. Although Fig. While Figure 3 depicts the switching element 342 as being contained within the driver module 306, in some examples the switching element 342 may be separate from the driver module 306. For example, the switching element 342 may be contained within switching modules 310. The charging pump 346 may be configured to boost a voltage supplied by the voltage source 302 using capacitors (not shown). As discussed below, the driver module 306 may be configured to drive a control voltage to the LED cells 112. Although the following discussion focuses on the driver module 306 operating with the LED cell 312A, it is understood that the driver module 306 can operate analogously with other LED cells of the LED cells 312. For example, the driver module 306 can be configured to drive a control voltage to the LED cell 312N when the switching module 310N couples the LED cell 312N to the driver module 306.

[0038] The operational amplifier 340 can include an output 350, an input 352, and an output 354. The operational amplifier 340 can be configured to drive a control voltage to the LED cells 312. For example, when the switching module 310A couples the LED cell 312A to the driver module 306, the operational amplifier 340 can supply a gate voltage (“GATE”). A “) Generate a control voltage across the capacitor 336A until a detection voltage (“SENSE”) is received at input 352 A “) of an LED voltage received at input 354 (“LED A ") corresponds.

[0039] The 310A switching module can contain switching elements 320A, 322A, and 324A. As discussed below, the 310A switching module can be configured to sequentially couple each of the 312 LED cells to the 306 driver module. Although the 310A switching module is discussed below, it should be understood that other 310 switching modules may be similar to the 310A switching module. For example, the 310N switching module can contain the 320N, 322N, and 324N switching elements, which are similar to the 320A, 322A, and 324A switching elements, respectively.

[0040] The switching modules 310 can be configured to sequentially couple each LED cell of the LED cells 312. For example, switching module 312A can activate (e.g., turn on) switching elements 320A, 322A, and 324A to couple LED cell 312A to driver module 306. When operational amplifier 340 applies a control voltage to capacitor 336A, switching module 312A can deactivate (e.g., turn off) switching elements 320A, 322A, and 324A to decouple LED cell 312A from driver module 306. After switching module 312A decouples LED cell 312A from driver module 306, switching module 312B (not shown) can couple LED cell 312B to driver module 306. When the operational amplifier 340 drives a control voltage across the capacitor at cell 312B (not shown), the switching module 312B can decouple the LED cell 312A from the driver module 306.The process of sequentially coupling each cell of the LED cells 312 can be repeated until the switching module 312N couples the LED cell 312N to the driver module 306. It is understood that the above can represent a single programming process. For example, the above can activate each LED cell of the LED cells 312 at the beginning edge of an "on" section of a duty cycle. Similarly, the circuit 300 can employ a similar process to deactivate each LED cell of the LED cells 312 at the beginning edge of an "off" section of the duty cycle.

[0041] The driver module 306 can generate a pulse-width modulation signal for programming the LED cells 312. For example, the driver module 306 can program the LED cell 312A to be "ON" (e.g., activated) by driving a current at a gate of the switching element 334A such that it corresponds to a non-zero reference current. For example, the driver module 306 can program the LED cell 312A to be "ON" (e.g., activated) by driving a current at a gate of the switching element 334A to 52 µA. Similarly, the driver module 306 can program the LED cell 312A to be "OFF" (e.g., deactivated) by driving a current at a gate of the switching element 334A such that it corresponds to a reference current of zero. Additionally or alternatively, the driver module 306 can program the LED cell 312A to "OFF" (e.g. deactivated) by short-circuiting the output 350 and the input 352, so that the gate of the switching element 332 and the source of the switching element 332 are short-circuited.

[0042] In some examples, the driver module 306 can program each of the LED cells 312 with substantially similar pulse-width modulation signals. For example, each of the LED cells 312A-312N can have a specific duty cycle. However, in other examples, the driver module 306 can program each of the LED cells 312 with a pulse-width modulation signal that is independent of the pulse-width modulation signals for other LED cells in the LED cell array 312. For example, the driver module 306 can program LED cell 312A to have a different pulse-width modulation signal than LED cells 312B-312N.

[0043] Fig. Figure 4 is a representation of an example switching signal 400 for sequential switching according to one or more techniques of this disclosure. As shown, the switching signal 400 includes the switching signals 460, 462, 464, and 466. For example, the switching signal 460 can be used to activate the switching elements 320A, 322A, and 324A of Fig. 3. The switching signal 462 can be used to activate the switching element 342 of Fig. 3. The switching signal 464 can be used to activate the switching elements 320B, 322B and 324B of Fig. 3 (not shown). The switching signal 466 can be used to activate the switching elements 320N, 322N and 324N of Fig. 3 will be determined. The control module 104 of Fig. 1 can generate the switching signals 460, 462, 464 and 466.

[0044] During the first programming state 470, the switching signal 460 activates the switching elements 320A, 322A and 324A of Fig. 3, the switching signal 462 deactivates the switching element 342 of Fig. 3, the switching signal 464 deactivates the switching elements 320B, 322B and 324B of Fig. 3, and the switching signal 466 deactivates the switching elements 320N, 322N and 324N of Fig. 3.

[0045] During the first switching state 472, the switching signal 460 deactivates the switching elements 320A, 322A and 324A of Fig. 3, the switching signal 462 activates the switching element 342 of Fig. 3, to use the operational amplifier 340 from Fig. To freeze 3, the switching signal 464 deactivates the switching elements 320B, 322B and 324B of Fig. 3, and the third switching element 466 deactivates the switching elements 320N, 322N and 324N of Fig. 3.

[0046] During the second programming state 474, the switching signal 460 deactivates the switching elements 320A, 322A and 324A of Fig. 3, the switching signal 462 deactivates the switching element 342 of Fig. 3, the switching signal 464 activates the switching elements 320B, 322B and 324B of Fig. 3, and the switching signal 466 deactivates the switching elements 320N, 322N and 324N of Fig. 3.

[0047] During the second switching state 476, the switching signal 460 deactivates the switching elements 320A, 322A and 324A of Fig. 3, the switching signal 462 activates the switching element 342 of Fig. 3, to use the operational amplifier 340 from Fig. To freeze 3, the switching signal 464 deactivates the switching elements 320B, 322B and 324B of Fig. 3, and the third switching element 466 deactivates the switching elements 320N, 322N and 324N of Fig. 3.

[0048] During the third programming state 478, the switching signal 460 deactivates the switching elements 320A, 322A and 324A of Fig. 3, the switching signal 462 deactivates the switching element 342 of Fig. 3, the switching signal 464 deactivates the switching elements 320B, 322B and 324B of Fig. 3, and the switching signal 466 activates the switching elements 320N, 322N and 324N of Fig. 3.

[0049] Fig. Figure 5 is a representation of a first programming state according to one or more techniques of this disclosure. As shown, the circuit 500 includes a voltage source 502, a driver module 506, switching modules 510A-510N (collectively switching modules 510 or switching module 510), and LED cells 512A-512N (collectively LED cells 512). The voltage source 502 can be an example of the voltage source 102 of Fig. 1. The driver module 506 can be an example of the driver module 106 from Fig. 1. The 512 LED cells can be an example of the 112 LED cells from Fig. 1. The 510 switching modules can be an example of the 110 switching modules from Fig. 1. The switching modules 510 and / or the LED cells 512 may be contained in an LED matrix component not shown.

[0050] The 506 driver module can replace the 306 driver module. Fig. 3. For example, the driver module 506, as shown, can contain an operational amplifier 540 with an output 550 and inputs 552 and 554, a switching element 542, a current source 544, and a charging pump 546, which are connected to the operational amplifier 340, the switching element 342, the current source 344, and the charging pump 346, respectively. Fig. 3 are essentially similar.

[0051] The 510 switching modules can be used with the 310 switching modules from Fig. 3. For example, as shown, the switching module 510A can contain the switching elements 520A, 522A and 524A, which correspond to the switching elements 320A, 322A and 324A respectively of Fig. 3 are essentially similar. Similarly, the switching module 510N can contain the switching elements 520N, 522N and 524N, which correspond to the switching elements 320N, 322N and 324N respectively of Fig. 3 are essentially similar.

[0052] The 512 LED cells can replace the 312 LED cells from Fig. 3. For example, as shown, the LED cell 512A can contain a switching element 532A, a switching element 534A, a capacitor 536A and an LED 538A, which correspond to the switching element 332A, the switching element 334A, the capacitor 336A and the LED 338A respectively. Fig. 3 are essentially similar. Similarly, the LED cell 512N can contain a switching element 532N, a switching element 534N, a capacitor 536N and an LED 538N, which correspond to the switching element 332N, the switching element 334N, the capacitor 336N and the LED 338N respectively. Fig. 3 are essentially similar.

[0053] During the first programming state of Fig. 5 (e.g., programming state 470 of Fig. 4) The switching module 510A couples the LED cell 512A to the driver module 506. For example, the switching element 520A can couple the output 550 of the operational amplifier 540 to the capacitor 536A, the switching element 522A can couple the input 552 of the operational amplifier 540 to a source of the switching element 534A, and the switching element 524A can couple the input 554 of the operational amplifier 540 to a source of the switching element 532A.

[0054] When the switching module 510A couples the LED cell 512A to the driver module 506, the operational amplifier 540 can "program" the control voltage across the capacitor 536A. For example, at the beginning edge of an "on" section of a duty cycle, the operational amplifier 540 can drive the control voltage across the capacitor 536A of the LED cell 512A to activate the LED 538A of the LED cell 512A. In particular, the driver module 506 can, for example, drive the control voltage of the LED cell 512A based on a reference current. For example, the driver module 506 can drive the control voltage of the LED cell 512A such that a current across the LED 548 corresponds to a reference current generated by the current source 544. For example, the driver module 506 can set a gate voltage ("GATE"). A “) increase at switching element 332A when a detection voltage received at input 552 (“SENSE”) is detected A “) over an LED voltage received at input 554 (“LED A“) is located. Similarly, the 506 driver module can supply a gate voltage (“GATE”). A “) decrease at switching element 332A when a detection voltage received at input 552 (“SENSE”) is detected A “) under an LED voltage received at input 554 (“LED A ") lies.

[0055] Fig. Figure 6 is a representation of a switching state according to one or more techniques of this disclosure. As shown, the circuit 600 includes a voltage source 602, a driver module 606, switching modules 610A-610N (collectively switching modules 610), and LED cells 612A-612N (collectively LED cells 612). The voltage source 602 can be an example of the voltage source 102 of Fig. 1. The driver module 606 can be an example of the driver module 106 from Fig. 1. The 612 LED cells can be an example of the 112 LED cells from Fig. 1. The 610 switching modules can be an example of the 110 switching modules from Fig. 1. The switching modules 610 and / or LED cells 612 may be contained in an LED matrix component not shown.

[0056] The 606 driver module can replace the 306 driver module. Fig. 3. For example, as shown, the driver module 606 can contain an operational amplifier 640 with an output 650 and inputs 652 and 654, a switching element 642, a current source 644, and a charging pump 646, which are connected to the operational amplifier 340, the switching element 342, the current source 344, and the charging pump 346, respectively. Fig. 3 are essentially similar.

[0057] The 610 switching modules can be used with the 310 switching modules from Fig. 3. For example, as shown, the switching module 610A can contain the switching elements 620A, 622A and 624A, which correspond to the switching elements 320A, 322a and 324A respectively of Fig. 3 are essentially similar. Similarly, the switching module 610N can contain the switching elements 620N, 622N and 624N, which correspond to the switching elements 320N, 322N and 324N respectively of Fig. 3 are essentially similar.

[0058] The 612 LED cells can replace the 312 LED cells. Fig. 3. For example, as shown, the LED cell 612 can contain a switching element 632A, a switching element 634A, a capacitor 636A and an LED 638A, which correspond to the switching element 332A, the switching element 334A, the capacitor 336A and the LED 338A respectively. Fig. 3 are essentially similar. Similarly, the LED cell 612N can contain a switching element 634N, a capacitor 636N and an LED 638N, which correspond to the switching element 332N, the switching element 334N, the capacitor 336N and the LED 338N respectively. Fig. 3 are essentially similar. Although shown as a single package, it is understood that components of the LED cells 612 can be formed on different substrates. For example, the LED 638A can be formed on a substrate different from a substrate containing the switching element 632A, the switching element 634A, and the capacitor 636A.

[0059] During the switching state of Fig. 6 (e.g., switch state 472 of Fig. 4) The switching modules 610 decouple the LED cells 612 from the driver module 606. For example, the switching element 620A can deactivate to decouple the output 650 of the operational amplifier 640 from the capacitor 636A, the switching element 622A can deactivate to decouple the input 652 of the operational amplifier 640 from a source of the switching element 634A, and the switching element 624A can deactivate to decouple the input 654 of the operational amplifier 640 from a source of the switching element 632A.

[0060] During the switching state of Fig. 6. The switching element 642 can couple the input 652 of the operational amplifier 640 to the input 654 of the operational amplifier 640. Although Fig. In Figure 6, the switching element 642 is shown to be contained within the driver module 606; however, in other examples, the switching element 642 may be separate. For instance, the switching element 642 may be contained within the switching modules 610. In any case, the driver module 606 can remain at a stable operating point because coupling input 652 to input 654 allows the operational amplifier 640 to output the gate voltage (“GATE”) generated at output 650. A “) maintains.

[0061] Fig. Figure 7 is a representation of a second programming state according to one or more techniques of this disclosure. As shown, the circuit 700 includes a voltage source 702, a driver module 706, switching modules 710A-710N (collectively switching modules 710), and LED cells 712A-712N (collectively LED cells 712). The voltage source 702 can be an example of the voltage source 102 of Fig. 1. The driver module 706 can be an example of the driver module 106 from Fig. 1. The 712 LED cells can be an example of the 112 LED cells from Fig. 1. The 710 switching modules can be an example of the 110 switching modules from Fig. 1. The switching modules 710 and / or the LED cells 712 may be contained in an LED matrix component not shown.

[0062] The 706 driver module can replace the 306 driver module. Fig. 3. For example, the driver module 706, as shown, can contain an operational amplifier 740 with an output 750 and inputs 752 and 754, a switching element 742, a current source 744, and a charging pump 746, which are connected to the operational amplifier 340, the switching element 342, the current source 344, and the charging pump 346, respectively. Fig. 3 are essentially similar.

[0063] The 710 switching modules can be used with the 310 switching modules from Fig. 3. For example, as shown, the switching module 710A can contain the switching elements 720A, 722A and 724A, which correspond to the switching elements 320A, 322a and 324A respectively of Fig. 3 are essentially similar. Similarly, the switching module 710N can contain the switching elements 720N, 722N and 724N, which correspond to the switching elements 320N, 322N and 324N respectively of Fig. 3 are essentially similar.

[0064] The 712 LED cells can replace the 312 LED cells from Fig. 3. For example, as shown, the LED cell 712 can contain a switching element 732A, a switching element 734A, a capacitor 736A and an LED 738A, which correspond to the switching element 332A, the switching element 334A, the capacitor 336A and the LED 338A respectively. Fig. 3 are essentially similar. Similarly, the LED cell 712N can contain a switching element 732N, a switching element 734N, a capacitor 736N and an LED 738N, which correspond to the switching element 332N, the switching element 334N, the capacitor 336N and the LED 338N respectively. Fig. 3 are essentially similar. Although shown as a single package, it is understood that components of the LED cells 712 can be formed on different substrates. For example, the LED 738A can be formed on a substrate different from a substrate containing the switching element 732A, the switching element 734A, and the capacitor 736A.

[0065] During the second programming state of Fig. 7 (e.g., programming state 478 of Fig. 4) The switching module 710A couples the LED cell 712N to the driver module 706. For example, the switching element 720N can couple the output 750 of the operational amplifier 740 to the capacitor 736N, the switching element 722N can couple the input 752 of the operational amplifier 740 to a source of the switching element 734N, and the switching element 724N can couple the input 754 of the operational amplifier 740 to a source of the switching element 732N.

[0066] When the switching module 710N couples the LED cell 712N to the driver module 706, the operational amplifier 740 can "program" the control voltage across the capacitor 736N. For example, at the beginning edge of an "on" section of a duty cycle, the operational amplifier 740 can drive the control voltage across the capacitor 736N of the LED cell 712N to activate the LED 738N on the LED cell 712N. In particular, the driver module 706 can, for example, drive the control voltage of the LED cell 712N based on a reference current. For example, the driver module 706 can drive the control voltage of the LED cell 712N such that a current across the LED 748 corresponds to a reference current generated by the current source 744. For example, the driver module 706 can set a gate voltage ("GATE"). N “) increase at switching element 332N when a detection voltage (“SENSE”) is received at input 752 N “) over an LED voltage received at input 754 (“LED N“) is located. Similarly, the 706 driver module can supply a gate voltage (“GATE”). N “) decrease at switching element 332N when a detection voltage received at input 752 (“SENSE”) is detected N “) under an LED voltage received at input 754 (“LED N ") lies.

[0067] Fig. Figure 8 is a circuit diagram representing a second example circuit 800 for mass LED cell programming according to one or more techniques of this disclosure. As shown, the circuit 800 includes a voltage source 802, a driver module 806, a switching module 810, and an LED cell 812. Although Fig. Since 8 represents an LED cell 812, it is understood that Fig. 8 can contain two or more LED cells that are essentially similar to the 812 LED cell. It is also understood that, although Fig. 8 represents a switching module, Fig. 8 can contain two or more switching modules that are substantially similar to switching module 810. Voltage source 802 can be an example of voltage source 102. Fig. 1. The driver module 806 can be an example of the driver module 106 from Fig. 1. The LED cells 812 can be an example of the LED cell 112A of the LED cells 112 from Fig. 1. The switching module 810 can be an example of the switching module 110A of the switching modules 110 from Fig. 1. The switching module 810 and / or the LED cell 812 may be contained in an LED matrix component not shown.

[0068] The 812 LED cells can be replaced by the 312A LED cells from Fig. 3. For example, as shown, the LED cell 812 can contain a switching element 832, a switching element 834, a capacitor 836 and an LED 838, which correspond to the switching element 332A, the switching element 334A, the capacitor 336A and the LED 338A respectively. Fig. 3 are essentially similar. Although shown as a single package, it is understood that components of the LED cell 812 can be formed on different substrates. For example, the LED 838 can be formed on a substrate different from a substrate containing the switching element 832, the switching element 834, and the capacitor 836.

[0069] The 806 driver module can be used similarly to the 306 driver module. Fig. 3. For example, as shown, the driver module 806 can contain an operational amplifier 840, a current source 844, and a charging pump 846, which connect to the operational amplifier 340, the current source 344, and the charging pump 346, respectively. Fig. 3 are essentially similar. However, as shown, the 806 driver module lacks a switching element.

[0070] The 810 switching module can be replaced by the 310A switching module. Fig. 3. For example, as shown, the switching module 810 can contain the switching elements 820, 822 and 824, which correspond to the switching elements 320A, 322A and 324A respectively of Fig. 3 are essentially similar. However, as shown, the switching module 810 still contains the switching element 842.

[0071] The switching module 810 can be configured to couple the LED cell 812 to the driver module 806. More specifically, for example, the switching element 842 can be configured to couple the current source 844 to a source of the switching element 834. Although the following discussion focuses on an operation using the switching module 810, it is understood that other switching modules may be similar to the switching module 810. For example, the switching module 810 can activate the switching elements 820, 822, 824, and 842 to couple the LED cell 812 to the driver module 806. When the operational amplifier 840 drives a control voltage across the capacitor 836, the switching module 810 can deactivate the switching elements 820, 822, 824, and 842 to decouple the LED cell 812 from the driver module 806. After the switching module 810 decouples the LED cell 812 from the driver module 806, another switching module (not shown) can couple another LED cell (not shown) to the driver module 806.As such, the 800 circuit can control the LED cells in essentially the same way as the 300 circuit. Fig. 3. Program.

[0072] Fig. Figure 9 is a flowchart for the mass LED cell programming that can be performed by a circuit according to this disclosure. For illustrative purposes only, the example operations below are presented within the context of System 100. Fig. 1, of the LED matrix component 208 of Fig. 2, of circuit 300 of Fig. 3, of the switching signal 400 from Fig. 4, of the circuit 500 of Fig. 5, of the circuit 600 of Fig. 6 and the circuit 700 from Fig. 7 described. However, the techniques described below can be used in any permutation and in any combination with the voltage source 102, the control module 104, the driver module 106 and an LED matrix component 108.

[0073] According to one or more techniques of this disclosure, the control module 104 determines a switching signal for the switching modules 110 (902). For example, the control module 104 generates a switching signal 400 from Fig. 4. In some examples, the control module 104 determines a first switching signal for the switching modules 110A with a first pulse width modulation signal. In this example, the control module 104 determines a second switching signal for switching modules 110A with a second pulse width modulation signal that is different from the first pulse width modulation signal.

[0074] The switching modules 110 sequentially couple each LED cell of the LED cells 112 to the driver module 106 using the switching signal to activate the LED cells 112 to ON or OFF according to a pulse width modulation signal state for each individual LED cell 112 (904). For example, during a first programming state, the switching module 110A couples LED cell 112A to the driver module 106. After the first programming state, the switching module 110A decouples LED cell 112A from the driver module 106. During a second programming state, the switching module 110A couples LED cell 112B to the driver module 106, and so on, until a programming state numbered "n", in which the switching module 110N couples LED cell 112N to the driver module 106.

[0075] Although not shown, the switching modules can couple 110 inputs on the driver module 106 during a switching state. For example, the switching element 342 of Fig. 3. Inputs 352 and 354 during each switching state between programming states.

[0076] The driver module 106 controls a control voltage at each LED cell during a program state such that a current at an LED of the respective LED cell corresponds to a reference current to activate the multiple LED cells (906). For example, the driver module 106 controls a control voltage at LED cell 112A during an initial programming state to activate LED cell 112A. Specifically, at the beginning edge of an "on" section of a duty cycle, the driver module 106 can drive a control voltage at LED cell 112A to activate an LED at LED cell 112A. After the driver module 106 drives the control voltage to activate the LED, a capacitor (e.g., a parasitic capacitor, a capacitor unit, etc.) maintains the control voltage to activate the LED at LED cell 112A during the "on" section of the duty cycle.When driving the control voltage at LED cell 112A, the driver module 106 drives a control voltage at LED cell 112B during a second programming state to activate LED cell 112B, etc., until the driver module 106 drives a control voltage at LED cell 112N to activate LED cell 112N during a programming state with the number "n".

[0077] The switching modules 110 sequentially couple each LED cell of the LED cells 112 to the driver module 106 using the switching signal to deactivate the LED cells 112 (908). For example, during a first programming state, the switching module 110A couples LED cell 112A to the driver module 106. After the first programming state, the switching module 110A decouples LED cell 112A from the driver module 106. During a second programming state, the switching module 110A couples LED cell 112B to the driver module 106, and so on, until a programming state numbered "n", in which the switching module 110N couples LED cell 112N to the driver module 106.

[0078] Although not shown, the switching modules can couple 110 inputs on the driver module 106 during a switching state. For example, the switching element 342 of Fig. 3. Inputs 352 and 354 during each switching state between programming states.

[0079] The driver module 106 controls a control voltage at each LED cell during a program state such that a current at an LED of the respective LED cell corresponds to a reference current to deactivate the multiple LED cells (910). For example, the driver module 106 controls a control voltage at LED cell 112A during a first programming state to deactivate LED cell 112A. Specifically, at the trailing edge of an "off" section of the duty cycle, the driver module 106 can drive the control voltage at LED cell 112A to deactivate an LED at LED cell 112A. After the driver module 106 drives the control voltage to deactivate the LED, the capacitance (e.g., parasitic capacitor, capacitor unit, etc.) maintains the control voltage to deactivate the LED at LED cell 112A during the "on" section of the duty cycle.When driving the control voltage at LED cell 112A, the driver module 106 drives a control voltage at LED cell 112B during a second programming state to deactivate LED cell 112B, etc., until the driver module 106 drives a control voltage at LED cell 112N to deactivate LED cell 112N during a programming state with the number "n".

[0080] Fig. Figure 10 is a representation of an example program time for a switching signal for mass LED cell programming according to one or more techniques of this disclosure. As shown, switching signal 1000 contains switching signals 1060, 1062, 1064, and 1066. For example, switching signal 1060 can be used to activate switching elements 320A, 322A, and 324A of Fig. 3. The switching signal 1062 can be used to activate the switching element 342 of Fig. 3. The switching signal 1064 can be used to activate the switching elements 320B, 322B and 324B of Fig. 3 (not shown). The switching signal 1066 can be used to activate the switching elements 320N, 322N and 324N of Fig. 3 will be determined. The control module 104 of Fig. 1 can generate the switching signals 1060, 1062, 1064 and 1066.

[0081] In the example of Fig. 10 can provide a total sampling time for the sequential switching of the LED cells 312 of Fig. 3 as program time (t p )+freezing time (t f ) multiplied by the number (n) of rows contained in an LED matrix component. To allow programming for a specific duty cycle, the control module 104 can generate the switching signal 1000 such that the total sampling time (e.g., program time (t)) is calculated. p )+freezing time (t f) multiplied by the number (n) of rows contained in an LED matrix component) is smaller than the smallest duty cycle (t p + t f = t r ) t r X n >t DC(min) .

[0082] Various aspects have been described in this disclosure. These and other aspects fall within the scope of protection of the following claims.

Claims

[1] Procedure, encompassing: Sequential coupling, by means of a switching module (110, 310, 510, 610, 710, 810) of a circuit (100, 300, 500, 600, 700, 800), of each cell of several cells (112, 312, 512, 612, 712, 812) to a driver module (110, 206, 306, 506, 606, 706, 806), wherein each cell of the several cells (112, 312, 512, 612, 712, 812) comprises a light-emitting diode (338, 538, 638, 738, 838) configured to be activated based on a control voltage at a respective cell; and Drive, by the driver module (110, 206, 306, 506, 606, 706, 806), the control voltage of a respective cell of the multiple cells (112, 312, 512, 612, 712, 812) based on a reference current, when the switching module (110, 310, 510, 610, 710, 810) sequentially couples a respective cell of the multiple cells (112, 312, 512, 612, 712, 812) to the driver module (110, 206, 306, 506, 606, 706, 806), wherein the driver module (110, 206, 306, 506, 606, 706, 806) comprises an operational amplifier (340, 540, 640, 740, 840), wherein the operational amplifier (340, 540, 640, 740, 840) has an output (350, 550, 650, 750), a first input (352, 552, 652, 752) and a second input (354, 554, 654, 752), and wherein the sequential coupling of each cell of the multiple cells (112, 312, 512, 612, 712, 812) to the driver module (110, 206, 306, 506, 606, 706, 806) The following includes: Coupling the output (350, 550, 650, 750), the first input (352, 552, 652, 752) and the second input (354, 554, 654, 752) to a respective cell of the multiple cells (112, 312, 512, 612, 712, 812) during the program state of the circuit (100, 300, 500, 600, 700, 800); and decoupling the operational amplifier (340, 540, 640, 740, 840) from each cell of the multiple cells (112, 312, 512, 612, 712, 812) and coupling the first input (352, 552, 652, 752) to the second input (354, 554, 654, 752) during a switching state of the circuit (100, 300, 500, 600, 700, 800). [2] Method according to claim 1, wherein driving the control voltage of the respective cell comprises: Driving the control voltage at the respective cell so that a current at the light-emitting diode (338, 538, 638, 738, 838) of the respective cell corresponds to the reference current. [3] Method according to claim 1 or 2, wherein the sequential coupling of each cell of the multiple cells (112, 312, 512, 612, 712, 812) to the driver module (110, 206, 306, 506, 606, 706, 806) comprises the following: Coupling a current source (344, 544, 644, 744, 844) configured to generate the reference current to each of the multiple cells during the program state of the circuit (100, 300, 500, 600, 700, 800). [4] Method according to any one of claims 1-3, wherein: Each cell of the multiple cells (112, 312, 512, 612, 712, 812) contains a switching element (332, 532, 632, 732, 832); the switching element (332, 532, 632, 732, 832) of each cell has at least one gate with a parasitic capacitance (336, 536, 636, 736); and the control voltage of the respective cell is applied to the gate of the switching element (332, 532, 632, 732, 832) of the respective cell. [5] Method according to any one of claims 1-4, wherein: Each cell of the multiple cells (112, 312, 512, 612, 712, 812) contains a switching element (332, 532, 632, 732, 832) with at least one gate; Each cell of the multiple cells (112, 312, 512, 612, 712, 812) contains a capacitor (336, 536, 636, 736) which is coupled to the gate of the switching element (332, 532, 632, 732, 832) of a respective cell; and the control voltage of the respective cell is applied to the capacitor (336, 536, 636, 736). [6] Method according to any one of claims 1-5, wherein the multiple cells (112, 312, 512, 612, 712, 812) are multiple first cells, the switching module (110, 310, 510, 610, 710, 810) is a first switching module, the driver module (110, 206, 306, 506, 606, 706, 806) is a first driver module, and the reference current is a first reference current, and the multiple first cells are arranged in a first column (209) of a light-emitting diode matrix device (208), the method further comprising: Sequential coupling, by means of a second switching module of the circuit (100, 300, 500, 600, 700, 800), of each cell of several second cells to a second driver module, wherein each cell of the several second cells comprises a light-emitting diode configured to be activated based on a control voltage at a respective cell, and wherein the several second cells are arranged in a second column (209) of the light-emitting diode matrix device (208); and Driving, by the second driver module, the control voltage of a respective cell of the several second cells based on a second reference current, when the second switching module sequentially couples a respective cell of the several second cells to the second driver module. [7] Circuit (100, 300, 500, 600, 700, 800), comprising: a driver module (110, 206, 306, 506, 606, 706, 806) configured to receive a reference current for multiple cells (112, 312, 512, 612, 712, 812), each cell of the multiple cells (112, 312, 512, 612, 712, 812) comprising a light-emitting diode (338, 538, 638, 738, 838) configured to be activated based on a control voltage at a respective cell of the multiple cells (112, 312, 512, 612, 712, 812); and a switching module (110, 310, 510, 610, 710, 810) configured to sequentially couple each cell of the multiple cells (112, 312, 512, 612, 712, 812) to the driver module (110, 206, 306, 506, 606, 706, 806), wherein the driver module (110, 206, 306, 506, 606, 706, 806) is further configured to drive a control voltage of a respective cell of the multiple cells (112, 312, 512, 612, 712, 812) based on the reference current, when the switching module (110, 310, 510, 610, 710, 810) sequentially couples a respective cell of the multiple cells (112, 312, 512, 612, 712, 812) to the driver module (110, 206, 306, 506, 606, 706, 806), wherein the driver module (110, 206, 306, 506, 606, 706, 806) comprises an operational amplifier (340, 540, 640, 740, 840), wherein the operational amplifier (340, 540, 640, 740, 840) has an output (350, 550, 650, 750), a first input (352, 552, 652, 752) and a second input (354, 554, 654, 752), and wherein for sequential coupling of each cell of the multiple cells (112, 312, 512, 612, 712, 812) to the driver module (110, 206, 306, 506, 606, 706, 806) the switching module (110, 310, 510, 610, 710, 810) is configured to: Coupling the output (350, 550, 650, 750), the first input (352, 552, 652, 752) and the second input (354, 554, 654, 752) to a respective cell of the multiple cells during the program state of the circuit (100, 300, 500, 600, 700, 800), and Decoupling the operational amplifier (340, 540, 640, 740, 840) from each cell of the multiple cells (112, 312, 512, 612, 712, 812) and coupling the first input (352, 552, 652, 752) to the second input (354, 554, 654, 752) during a switching state of the circuit (100, 300, 500, 600, 700, 800). [8] Circuit (100, 300, 500, 600, 700, 800) according to claim 7, wherein the driver module (110, 206, 306, 506, 606, 706, 806) is further configured to drive the control voltage of the respective cell: Driving the control voltage at the respective cell so that a current at the light-emitting diode (338, 538, 638, 738, 838) of the respective cell corresponds to the reference current. [9] Circuit (100, 300, 500, 600, 700, 800) according to claim 7 or 8, wherein the switching module (110, 310, 512, 612, 712, 812) is configured to sequentially couple each cell of the multiple cells (112, 312, 512, 612, 712, 812) to the driver module (110, 206, 306, 506, 606, 706, 806): Coupling a current source configured to generate the reference current to each of the multiple cells (112, 312, 512, 612, 712, 812) during the program state of the circuit (100, 300, 500, 600, 700, 800). [10] Circuit (100, 300, 500, 600, 700, 800) according to any one of claims 7-9, further comprising: the multiple cells (112, 312, 512, 612, 712, 812), wherein each cell of the multiple cells (112, 312, 512, 612, 712, 812) contains a switching element (332, 532, 632, 732, 832), wherein the switching element (332, 532, 632, 732, 832) contains at least one gate with a parasitic capacitance (336, 536, 636, 736), the control voltage of the respective cell is applied to the gate of the switching element (332, 532, 632, 732, 832) of the respective cell. [11] Circuit (100, 300, 500, 600, 700, 800) according to any one of claims 7-10, further comprising: the multiple cells (112, 312, 512, 612, 712, 812), wherein each cell of the multiple cells (112, 312, 512, 612, 712, 812) contains a switching element (332, 532, 632, 732, 832) with at least one gate, and each cell of the multiple cells (112, 312, 512, 612, 712, 812) contains a capacitor (336, 536, 636, 736) coupled to the gate of the switching element (332, 532, 632, 732, 832) of the respective cell, the control voltage of the respective cell is applied to the capacitor (336, 536, 636, 736) of the respective cell. [12] Circuit (100, 300, 500, 600, 700, 800) according to any one of claims 7-11, wherein the multiple cells (112, 312, 512, 612, 712, 812) are multiple first cells, the switching module (110, 310, 510, 610, 710, 810) is a first switching module, the driver module (110, 206, 306, 506, 606, 706, 806) is a first driver module, the reference current is a first reference current, and the multiple first cells are arranged in a first column of a light-emitting diode matrix device, wherein the circuit (100, 300, 500, 600, 700, 800) further comprises: a second driver module configured to receive a second reference current for several second cells, each cell of the several second cells comprising a light-emitting diode (338, 538, 638, 738, 838) configured to be activated based on a control voltage at a respective cell of the several second cells, and the several second cells being arranged in a second column of the light-emitting diode matrix device; and a second switching module configured to sequentially couple each of the multiple second cells to the second driver module, wherein the second driver module is still configured to drive a control voltage of a respective cell of the multiple second cells based on the second reference current, when the second switching module sequentially couples a respective cell of the multiple second cells to the second driver module.

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