Systems and devices for LED communication control

Abstract

A light-emitting diode (LED) module includes one or more LEDs; communication circuitry configured to communicate with a plurality of LED modules using differential signaling; an input port and an output port for communicating using the differential signaling; testing circuitry configured to test a differential signaling connection through the input port or output port to determine a connection failure between the LED module and a neighboring LED module of the plurality of LED modules. The communication circuitry is configured to selectively switch, in response to the testing circuitry determining a connection failure of the differential signaling connection with the neighboring LED module, from communicating using differential signaling to communicating using single- ended signaling with the neighboring LED module.

Description

[0001] SYSTEMS AND DEVICES FOR LED COMMUNICATION CONTROL

[0002] Field

[0003] This present disclosure generally relates to LED lighting communication .

[0004] Background

[0005] RGBI LEDs are a type of light emitting diode ( LED) with an integrated LED driver and a communication integrated circuit ( IC) that can be used to control a large number of light sources .

[0006] FIG . 1A shows an example a network 100 . The network 100 includes a host 110 and a plurality of nodes 120 . The host 110 can be a microcontroller or microcontroller unit (MCU) . As shown in FIG . IB, each node 120 can be a LED unit or LED module including red, green, and blue emitters 130 , an LED driver 140 , and a communication circuitry or communication interface circuitry 160 , and input and output ports 165a and 165b, all which can be combined in one package . As shown, the MCU 110 is coupled to the nodes 120 in a daisy chain topology . ( FIG . 2A shows examples of common network topologies ) . Since differential signaling is used, there are 2 connections 150 between the nodes 120 or between host 110 and the nodes 120 . The 2 connections can include wire connections .

[0007] The network 100 can be controlled by the host 110 which sends transmissions to the first node in the chain . The first node will accept the data if it is targeted at this node or forward the data to the next node if it is targeted at another node . During forwarding, the data is typically retimed and buffered . This mechanism can allow for efficient forwarding of the data between up to hundreds of nodes without loss of data integrity .

[0008] For automotive purposes , the data connection (physical ) is typically using low-voltage-differential signaling ( LVDS ) based on two lines to improve electromagnetic compatibility . One challenge of the daisy chain topology is that it is less robust towards interruption of the network connection . These could, for example , stem from broken connections such as a broken bond wire or a lifted solder j oin that disrupts the connection .

[0009] Two factors which are disadvantageous for a daisy chain network topology, compared to a simpler star topology network are

[0010] • Occurrence : The number of connections / j oints is higher, increasing the statistical likelihood of a failure

[0011] • Impact : A broken j oint will disable the remaining part of the chain, instead of only one node .

[0012] FIG . 2B includes a graph 200 that shows the failure rate for different network topologies , ( star 210 , single daisy chain 220 , differential signaling daisy chain 230 ) assuming a j oint failure rate of 1 ppm per j oint . Since differential signaling uses twice as many connections / j oint as a simple daisy chain, the failure is twice as high .

[0013] Description

[0014] In the drawings , like reference characters generally refer to the same parts throughout the different views . The drawings are not necessarily to scale , emphasis instead generally being placed upon illustrating the principles of the disclosure . In the following description, various aspects of the disclosure are described with reference to the following drawings , in which :

[0015] FIG . 1A shows an example of a network 100 including a host 110 and a plurality of nodes 120 ;

[0016] FIG . IB shows an example of LED node or module ;

[0017] FIG . 2A shows examples of common network topologies ; FIG . 2B includes a graph showing the failure rate for different network topologies of FIG . 2A;

[0018] FIG . 3 an example network in a daisy chain configuration according to aspects of the present disclosure ;

[0019] FIG . 4 example of a node according to aspects of the present disclosure ;

[0020] FIG . 5 to FIG . 6 illustrates examples of a part of a daisy chain network of nodes according to aspects of the present disclosure ;

[0021] FIG . 7 illustrates a method of controlling communications in a light-emitting diode (LED) module arranged in a daisy chain network topology according to aspects of the present disclosure .

[0022] The following detailed description refers to the accompanying drawings that show, by way of illustration, specific details and aspects in which the disclosure may be practiced . One or more aspects are described in sufficient detail to enable those skilled in the art to practice the disclosure . Other aspects may be utilized and structural , logical , and electrical changes may be made without departing from the scope of the disclosure . The various aspects described herein are not necessarily mutually exclusive , as some aspects can be combined with one or more other aspects to form new aspects . Various aspects are described in connection with methods and various aspects are described in connection with devices . However, it may be understood that aspects described in connection with methods may similarly apply to the devices , and vice versa . Throughout the drawings , it should be noted that like reference numbers are used to depict the same or similar elements , features , and structures . Throughout the drawings , it should be noted that proportions are not necessary to scale and that the size of features may be emphasized for ease of illustration . FIG . 3 shows examples network 300a and 300b in a daisy chain configuration . The network 300a may be the same or similar as the network 100 of FIG . 1A in that it includes a host or MCU 310 that is coupled in daisy chain configuration with nodes 320 . The nodes 320 may be any suitable node , such as the node 120 of FIG . 1A and FIG . IB .

[0023] The MCU 310 and the nodes 320 can communicate using differential signaling such as LVDS . As such, a pair of connections 350 exist between neighboring nodes and between the host 310 and a neighboring node 320 .

[0024] In the example of FIG . 3 , the network 300a may have a broken or malfunctioning connection 380 .

[0025] According to at least one embodiment can utilize the fact that a differential signaling connection can be based on two connections , e . g . , two wires . While a functioning differential signaling connections or links can require two wires , it is still possible to transmit the same information using a single ended connection by using voltage based signaling .

[0026] Accordingly, the network 300b can be the network 300a except the nodes having the broken dif ferential signaling connection therebetween can communicate with each other using a single ended communication mode .

[0027] In accordance with at least one aspect of the present disclosure , the network or at least one node ( e . g . , LED unit / LED module ) can detect the broken j oint or broken connection and then in response to the detection of the broken connection can switch to communicating using a single-ended communication mode . This effectively allows the system to operate normally even in presence of a single j oint failure . The probability of a double broken j oint is drastically lower .

[0028] Despite single ended ( SE) communication being more prone to EMI issues , switching a single link within a large system to SE communication would still main a low overall EMI emission . Further, a network can be designed with detectable mode switch with an upper limit for allowable SE nodes within a system.

[0029] Therefore , in aspects of the present disclosure , networks such as the network 300a / 300b or 100 can include nodes with circuitry to detect broken connections , e . g . , broken differential signaling connections , and circuitry to switch to SE communication .

[0030] FIG . 4 shows an example of a node according to aspects of the present disclosure . For example , the nodes 320 or nodes of other networks ( e . g . , daisy chain topology networks using differential signaling communications ) may implemented be the same or similar to the node 400 .

[0031] In one or more examples , the node 400 may be an LED module or LED unit . For example , each may include one or more LEDs 430 , and a communication circuitry 460 configured to communicate with at least one other LED unit using differential signaling, such as LVDS , an input port 465a and an output port 465b for communicating using differential signaling . The input port 465a and 465b may be implemented to separately or independently connect to each wire that forms a part of the differential signaling connection pair for the dif ferential signaling connection .

[0032] In addition, node 400 includes testing circuitry 470 configured to test a dif ferential signaling connections through the input port or output port in order to detect any connection failure of a differential signaling connection . The communication circuitry 460 can be further configured, in response to the testing circuitry determining a failure of the differential signaling connection, to switch from communicating using differential signaling to communicating using single-ended signaling .

[0033] As noted, the differential signaling connections includes a differential connection pair ( e . g . , two wires ) . Accordingly, the testing circuitry 470 can be configured to test each of the differential connection pair . For example , the testing circuitry 470 can determine or be configured to determine a failure in the differential signaling connection by determining a connection break or connection failure in at least one connection of the differential connection pair .

[0034] In one case , the testing circuitry 470 determining a connection break or connection failure by the testing circuitry 470 determining a short or short fault in at least one connection of the differential connection pair . In other cases , an open fault may be detected by the testing circuitry 470 .

[0035] Further, the communication circuitry 470 is configured to switch from communicating using dif ferential signaling to communicating using single-ended signaling .

[0036] FIG . 5 shows a part of a daisy chain network 400 of nodes according to at least one example of the present disclosure . Specifically, aspects of two adj acent or neighboring nodes 420a, 420b in a daisy chain network topology are shown . For example , communication circuitry 460 of the node 420a is shown in form of a driver circuit . The driver circuitry aspect of the communication circuitry 460 communicates using differential signaling through the differential signaling connection 450 which includes a differential pair ( e . g . , pair of wires ) to the node 420b .

[0037] The node 420b receives dif ferential signaling communications from the node 420a . Aspects of the communication circuitry 460 and the testing circuitry 470 of the node 420b are depicted in FIG . 5 . As shown, the communication circuitry 460 of the node 420b includes a receiver 462 for receiving differential signaling communications or differential signaling signals , e . g . , from an input port . In one example the receiver 462 may be a comparator with each differential input coupled one of the differential pair of connections of the differential signaling connection . Further, a load, such as a resistor or other suitable element may be provided between the differential inputs of the receiver 462 to form a current loop . The communication circuitry can be configured to generate a differential output from the input it receives .

[0038] The testing circuitry 470 includes a s circuit 472 coupled to the input port and configured to test the differential signaling connection through the input port to the differential connection pair . The comparator circuit 472 can be a Schmitt trigger circuit or other suitable circuit arranged in a feedback arrangement where input port couples to one of the inputs of the comparator circuit 472 . As shown, one of the differential connection pairs of the dif ferential signaling connection is coupled to an input of the comparator circuit 472 .

[0039] Further, the output of the comparator circuit 472 is arranged to be fed back into to one of the inputs of one of the receiver 462 . Accordingly, the comparator circuit 472 , is configured to determine a failure in response by determining that the input ( e . g . , the differential connection pair) has been pulled high or pulled low from a common mode voltage .

[0040] The communication circuitry 460 is configured, in response to the testing circuitry 470 determining a connection break / f ailure to switch to communicating using differential signaling with the node 420a . That is , the communication circuitry 460 , e . g . , the receiver 462 is configured to pull the input of the differential signaling connection to polarity opposite its current polarity in response .

[0041] The feedback or output from the testing circuitry 470 , e . g . , the Schmitt trigger circuit when there is connection break is detected because the Schmitt trigger reacts to a break in the current loop of the receiver 462 . In normal circumstances , a fixed voltage can exist between the inputs of the receiver 462 which forms part of the current loop . When there is a connection break ( e . g . , a fault ) there is a change in the fixed voltage in the current loop which can be detected by Schmitt trigger circuit . The testing circuitry 470 or Schmitt trigger produces an output based on the change to the current loop to the differential signaling input causes a change in the differential voltage at the input which causes the communication circuitry 460 , namely the receiver 462 to pull the input in an opposite polarity . As a result , the receiver allows the communication circuitry 460 to operate in a single-ended signaling mode and produces single-ended outputs , which can be further processed by the node 460 . Hence , the node 460b can be configured after the connection failure detection or determination to received single-ended signaling communications from the node 460a .

[0042] In general , if one wire of the differential signaling connections ( e . g . , one of the dif ferential signaling wires ) breaks , the driver or communication circuitry 460 of node 420a will pull the receiver input of the receiver 462 or node 420b to source (VDD) or ground (GND) instead of the common mode voltage . The testing circuit 470 of node 420b is configured to detect this connection break with a comparator circuit, e . g . , a Schmitt trigger, and the receiver 462 is configured to pull the input in the opposite direction, which allows binary SE communication .

[0043] Since the signal at the receiver 462 can occur in inverted or noninverted form, depending on which j oint broke , a polarity detection circuit can be introduced 480 , for example in a clock and data recovery circuit . This can be implemented with a suitable preamble . For example , the polarity detection circuit 480 can be part of the digital domain after the receiver . It would use a preamble ( first word in data packet with a unique bit sequence , e . g . , 01000101 that allows detection of start and polarity) to identify the polarity of the data packet and decode the remaining data accordingly .

[0044] The benefits of the nodes or LED units such as described in connection with node 460b is that it can react to open j oints on the fly and would also allow to circumvent intermittent j oint failures . This type of implementation to switch to SE communication in FIG . 5 may be considered a passive type of implementation .

[0045] FIG . 6 shows a part of a daisy chain network 400 according to at least one example of the present disclosure . Specifically, aspects of two adj acent or neighboring nodes 420a, 420b in a daisy chain network topology are shown . For example , communication circuitry 460 of the node 420a is shown in form of a driver circuit . The driver circuitry part of the communication circuitry 460 helps the node 420a communicate using differential signaling through the differential signaling connection 450 (e . g . , differential pair of connections / wires ) to the node 420b .

[0046] In addition, the node 400 of FIG . 6 includes testing circuitry 470 . For example , the test circuitry 470 can modify the behavior of the driver circuitry 464 . In at least one example , the driver circuitry 464 can perform an active test .

[0047] For example , testing circuitry or element 470 may include push pull drivers that are activated when an open line is detected . Further, the testing circuitry 470 may also include a sensing circuit including one or more additional Schmitt triggers .

[0048] In one example , the testing circuitry 470 can be configured to test current flow through the output port sent by the driver circuitry . Based on the amount of current flow detected, the testing circuitry 470 can determine a connection failure of the differential signaling connection / wires such by detecting an open fault or a short fault on the differential signaling connection ( e . g . , differential wire pair) . As shown in the FIG 6, the testing circuitry 470 can be coupled the dif ferential signaling connection / wires to sense or detect the current flow of the differential signaling connection .

[0049] In response to determining a connection failure of the differential signaling connection, the test circuitry 470 can cause the driver circuitry 464 to transmit certain signals such as a command sequence to the next node 420b upon detection or determination of a connection failure ( e . g . , short fault, open fault , etc . ) . The command sequence sent to the node 420b can be interpreted, for example , by the receiver 462 of the node 420b to cause the node 420b or communication circuitry 460 thereof to operate using single ended communication .

[0050] Further, the communication circuitry, e . g . , the driver circuitry 472 is configured to switching from communicating using differential signaling to communicating using single- ended signaling by the driver circuitry switching to a push / pull driving mode . The switch by the driver circuitry 424 to push-pull driving mode for singled-ended communication may occur in response to a command or signal from the testing circuitry 470 .

[0051] Further, the testing circuitry 470 may cause the communication circuitry 460 / the driver circuitry 464 to output a message indicating a switch to single-ended signaling communication mode in event the driver 464 switches to communicating using single-ended signaling .

[0052] The approach described in connection with FIG . 6 allows for better control of voltage levels on line since proper push / pull drivers are used .

[0053] FIG . 7 is a flow diagram of a method 700 of controlling communications in a light-emitting diode ( LED) module arranged in a daisy chain network topology, the LED module configured to communicate using a differential signaling .

[0054] The method 700 includes at 710 , testing a differential signaling connection of the LED module . At 720 , the method 700 further includes determining a connection failure in a differential connection used for differential signaling . At 730 , the method includes switching from communicating using differential signaling to communicating using single-ended signaling . In general , embodiments or examples described in the present disclosure relate to nodes in a daisy chain network topology using differential signaling . The nodes can detect broken j oints and switch to a single ended connection mode for those links . This effectively allows the system to operate normally even in presence of a single j oint failure . The probability of a double broken j oint is drastically lower .

[0055] [EXAMPLE SECTION - GENERAL CLAIM SET]

[0056] In the following some examples are described, which relate to what is described herein and shown in the figures .

[0057] Example 1 is a light-emitting diode ( LED) module , comprising : one or more LEDs ; communication circuitry configured to communicate with at least one other LED module using differential signaling; an input port and an output port for communicating using the differential signaling; testing circuitry configured to test a dif ferential signaling connection through the input port or output port to determine a connection failure ; wherein the communication circuitry is configured to switch, in response to the testing circuitry determining a connection failure of the differential signaling connection, from communicating using LVDS to communicating using single-ended signaling .

[0058] Example 2 is the subj ect matter of Example 1 , wherein the differential signaling connection may include a differential connection pair, and wherein the testing circuitry is configured to test each connection of the differential connection pair .

[0059] Example 3 is the subj ect matter of Example 2 , wherein determining a failure in the differential signaling connection may include determining a connection break in at least one connection of the differential connection pair . Example 4 is the subj ect matter of Example 2 or 3 , wherein determining a failure in the differential signaling connection may include determining a short fault in at least one connection of the differential connection pair .

[0060] Example 5 is the subj ect matter of any of Example 1 to 4 , wherein the communication circuitry may include a receiver for receiving differential signaling communications from the input port, wherein the testing circuitry a comparator circuit coupled to the input port and configured to test the LVDS connection through the input port .

[0061] Example 6 is the subj ect matter of Example 5 , wherein the comparator circuit may be configured to determine a failure in response to determining that the input has been pulled high or pulled low from a common mode voltage .

[0062] Example 7 is the subj ect matter of Example 6, wherein the communication circuitry configured to switch from communicating using differential signaling to communicating using single- ended signaling may include the comparator circuit configured to pull the input to an opposite polarity to its current polarity .

[0063] Example 8 is the subj ect matter of any of Example 1 to 5 , wherein the communication circuitry may include a driver circuitry for communicating using differential signaling and; wherein testing circuitry is configured to test differential signaling connection through the output port comprising the testing circuitry to test current flow through the output port .

[0064] Example 9 is the subj ect matter of Example 8 , wherein the testing circuitry configured to test current flow through the output port may include the testing circuitry to determine whether an open fault or short fault condition exists at the output port . Example 10 is the subj ect matter of Example 8 or 9 , wherein the communication circuitry may be configured to switching from communicating using differential signaling to communicating using single-ended signaling comprises the driver circuitry switching to a push / pull driving mode .

[0065] Example 11 is the subj ect matter of Example 10 , wherein the driver circuitry may be further configured to output a message indicating a switch to single-ended signaling communication mode in event the driver circuitry switches to single-ended signaling .

[0066] Example 12 is the subj ect matter of any of Examples 1 to 11 , wherein the differential signaling may include low voltage differential signaling (LVDS ) .

[0067] Example 13 is an arrangement which may include : a series of light-emitting diode (LED) modules arranged in a daisy chain network topology, each LED module , comprising any of the LED modules of Examples 1 to 12 .

[0068] Example 14 is the subj ect matter of Example 13 , which may further include : a microcontroller unit coupled to the series of LED modules , wherein the microcontroller and the series of LED modules are arranged in daisy chain network topology .

[0069] Example 1A is a method of controlling communications in a light-emitting diode ( LED) module arranged in a daisy chain network topology, the LED module configured to communicate using a differential signaling, the method including : testing a dif ferential signaling connection of the LED module ; determining a connection failure in a differential connection used for differential signaling; and switching from communicating using dif ferential signaling to communicating using single-ended signaling .

[0070] Example 2A is the subj ect matter of Example 1A, wherein the differential signaling connection may include a pair of wires , wherein determining the connection failure testing each wire of the pair of wires of the differential signaling connection .

[0071] Example 3A is the subj ect matter of Example 2A, wherein determining a connection failure may include determining a connection failure a single wire of the differential signaling connection .

[0072] Example 4A is the subj ect matter of Example 3A, wherein determining a connection failure in a single wire of the differential signaling connection may include determining an open fault the single wire .

[0073] Example 5A is the subj ect matter of Example 3A, wherein determining a connection failure in a single wire of the differential signaling connection may include determining a short fault in the single wire .

[0074] Example 6A is the subj ect matter of any of Examples 1A to 5A, wherein the LED module may include a receiver for receiving communications through the differential signaling connection .

[0075] Example 7A is the subj ect matter of Example 6A, wherein the LED module may include a comparator circuit coupled to a receiver input of the dif ferential signaling connection, wherein testing comprises detecting a failure using the comparator circuit .

[0076] Example 8A is the subj ect matter of Example 7A, wherein determining a failure may include determining using the comparator circuit to determine that the receiver input of the differential signaling connection has been pulled high or pulled low from a common mode voltage .

[0077] Example 9A is the subj ect matter of Example 8A, wherein switching from communicating using dif ferential signaling to communicating using single-ended signaling may include the receiving pulling the receiver input from differential connection to an opposite polarity from its current polarity . Example 10A is the subj ect matter of Example 7A, wherein the LED module may include a current loop at the receiver input , and wherein testing the differential signaling connection may include determining a connection failure in the current loop .

[0078] Example 11A is the subj ect matter any of Examples 1A to 5A, wherein the LED module may include a driver circuitry for communicating using differential signaling and testing circuitry for testing the dif ferential signaling connection; wherein testing the differential connection may include testing current flow through the differential connection to determine short faults or connections breaks in the signaling connection .

[0079] Example 12A is the subj ect matter of Example 11A, wherein switching from communicating using dif ferential signaling to communicating using single-ended signaling may include the driver circuitry switching to a push / pull driving mode and outputting a message indicating a switch to single-ended signaling .

[0080] Example 13A is the subj ect matter of Example 3A, which may further include detecting the polarity of a wire of the differential connection not determined to have a connection failure ; communicating using singled-ended communication using the wire detected not determined to have a connection failure based on the detected polarity .

[0081] Example 14A is the subj ect matter of any of Examples 1A to 13A, wherein the differential signaling may be a low-voltage differential signaling (LVDS ) , and wherein the differential signaling connection may be a LVDS connection .

[0082] The examples described herein may be suitably and appropriately combined with each other .

[0083] The word "exemplary" is used herein to mean "serving as an example , instance , or illustration . " Any example or design described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other examples or designs .

[0084] The words "plurality" and "multiple" in the description or the claims expressly refer to a quantity greater than one. The terms "group (of)", "set [of]", "collection (of)", "series (of)", "sequence (of)", "grouping (of)", etc., and the like in the description or in the claims refer to a quantity equal to or greater than one, i.e., one or more. Any term expressed in plural form that does not expressly state "plurality" or "multiple" likewise refers to a quantity equal to or greater than one .

[0085] The term "connected" can be understood in the sense of a (e.g., mechanical, optical and / or electrical) , e.g. direct or indirect, connection and / or interaction. For example, several elements can be connected together mechanically such that they are physically retained (e.g., a plug connected to a socket) and electrically such that they have an electrically conductive path (e.g., signal paths exist along a communicative chain) .

[0086] As used herein, unless otherwise specified the use of the ordinal adjectives "first", "second", "third" etc., to describe a common object, merely indicate that different instances of like objects are being referred to and are not intended to imply that the objects so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner.

[0087] As utilized herein, terms "module", "component," "system," "circuit, " "element, " "slice, " "circuitry, " and the like are intended to refer to a set of one or more electronic components, a computer-related entity, hardware, software (e.g., in execution) , and / or firmware. For example, circuitry or a similar term can be a processor, a process running on a processor, a controller, an object, an executable program, a storage device, and / or a computer with a processing device. By way of illustration, an application running on a server and the server can also be circuitry. One or more circuits can reside within the same circuitry, and circuitry can be localized on one computer and / or distributed between two or more computers . A set of elements or a set of other circuits can be described herein, in which the term " set" can be interpreted as "one or more . "

[0088] Such electric or electronic circuitry can be operated by a software application or a firmware application executed by one or more processors . The one or more processors can be internal or external to the apparatus and can execute at least a part of the software or firmware application . As yet another example , circuitry can be an apparatus that provides specific functionality through electronic components without mechanical parts ; the electronic components can include one or more processors therein to execute executable instructions stored in computer readable storage medium and / or firmware that confer ( s ) , at least in part , the functionality of the electronic components . As another example , circuitry or similar term can be implemented in hardware such as application specific integrated circuit (ASIC) , programmable gate array ( PGA) , discrete digital circuits , etc . ) or in a combination of hardware and software ( e . g . , a software model executed by a corresponding processor) .

[0089] The term "data" as used herein may be understood to include information in any suitable analog or digital form, e . g . , provided as a file , a portion of a file , a set of files , a signal or stream, a portion of a signal or stream, a set of signals or streams , and the like . Further, the term "data" may also be used to mean a reference to information, e . g . , in form of a pointer . The term data, however, is not limited to the aforementioned examples and may take various forms and represent any information as understood in the art .

[0090] As used herein, a signal that is "indicative of" a value or other information may be a digital or analog signal that encodes or otherwise communicates the value or other information in a manner that can be decoded by and / or cause a responsive action in a component receiving the signal . The signal may be stored or buf fered in computer readable storage medium prior to its receipt by the receiving component and the receiving component may retrieve the signal from the storage medium. Further, a "value" that is "indicative of" some quantity, state , or parameter may be physically embodied as a digital signal , an analog signal , or stored bits that encode or otherwise communicate the value .

[0091] As used herein, a signal may be transmitted or conducted through a signal chain in which the signal is processed to change characteristics such as phase , amplitude , frequency, and so on . The signal may be referred to as the same signal even as such characteristics are adapted . In general , so long as a signal continues to encode the same information, the signal may be considered as the same signal . For example , a transmit signal may be considered as referring to the transmit signal in baseband, intermediate , and radio frequencies .

[0092] While the above descriptions and connected figures may depict device components as separate elements , skilled persons will appreciate the various possibilities to combine or integrate discrete features , functions into a single element . Such may include combining two or more components into a single component . Conversely, skilled persons will recognize the possibility to separate a single element into two or more discrete elements , such as splitting a single component into two or more separate components .

[0093] It is appreciated that implementations of methods detailed herein are exemplary in nature , and are thus understood as capable of being implemented in a corresponding device . Likewise , it is appreciated that implementations of devices detailed herein are understood as capable of being implemented as a corresponding method . It is thus understood that a device corresponding to a method detailed herein may include one or more components configured to perform each aspect of the related method . All acronyms defined in the above description additionally hold in all claims included herein .

[0094] While the disclosure has been particularly shown and described with reference to specific embodiments , it should be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the disclosure as defined by the appended claims . The scope of the disclosure is thus indicated by the appended claims and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced .

[0095] Reference Numeral List node network host / MCU node / LED unit light emitters LED driver communication connection communication circuitry a input port b output port graph star network topology single daily chain network topology differential signaling daisy chain network topologya, 300b network in daisy chain network topology host / microcontroller unit nodes ( LED modules / LED units ) differential signaling connection node ( LED module / LED unit ) light emitters / light emitting diodes light driver / LED driver communication circuitry receiver / receiver circuitry driver circuitry comparator circuit / Schmitt trigger circuit a input port b output port testing circuitry polarity detection circuit

Claims

CLAIMS1 . A light-emitting diode (LED) module , comprising : one or more LEDs ; communication circuitry configured to communicate with a plurality of LED modules using differential signaling; an input port and an output port for communicating using the differential signaling; testing circuitry configured to test a differential signaling connection through the input port or output port to determine a connection failure between the LED module and a neighboring LED module of the plurality of LED modules ; wherein the communication circuitry is configured to selectively switch, in response to the testing circuitry determining a connection failure of the differential signaling connection with the neighboring module , from communicating using differential signaling with the neighboring LED module to communicating using single-ended signaling with the neighboring LED module .2 . The LED module of claim 1 wherein the differential signaling connection comprises a differential connection pair, and wherein the testing circuitry is configured to test each connection of the differential connection pair .3 . The LED module of claim 2 , wherein determining a failure in the differential signaling connection comprises determining a connection break in at least one connection of the differential connection pair .4 . The LED module of claim 2 or 3 , wherein determining a failure in the differential signaling connection comprises determining a short fault in at least one connection of the differential connection pair .5 . The LED module of any of claims 1 to 4 ,wherein the communication circuitry comprises a receiver for receiving differential signaling communications from the input port, wherein the testing circuitry a comparator circuit coupled to the input port and configured to test the differential signaling connection through the input port .

6. The LED module of claim 5 , wherein the comparator circuit is configured to determine a failure in response to determining that the input has been pulled high or pulled low from a common mode voltage .7 . The LED module of claim 6, wherein the communication circuitry is configured to switch from communicating using differential signaling to communicating using single-ended signaling comprises the comparator circuit configured to pull the input to an opposite polarity to its current polarity .8 . The LED module of any of claims 1 to 5 , wherein the communication circuitry comprises a driver circuitry for communicating using differential signaling and; wherein testing circuitry is configured to test differential signaling connection through the output port comprising the testing circuitry to test current flow through the output port .9 . The LED module of claim 8 , wherein the testing circuitry is configured to test current flow through the output port comprises the testing circuitry to determine whether an open fault or short fault condition exists at the output port .10 . The LED module of claim 8 or 9 , wherein communication circuitry is configured to switching from communicating using differential signaling to communicating using single-ended signaling comprises the driver circuitry switching to a push / pull driving mode .11 . The LED module of claim 10 , wherein the driver circuitry is further configured to output a message indicating a switch to single-ended signaling communication mode in event the driver circuitry switches to single-ended signaling .12 . The LED module of any of claims 1 to 11 , wherein the differential signaling comprises low voltage differential signaling (LVDS ) .13 . An arrangement comprising : a series of light-emitting diode (LED) modules arranged in a daisy chain network topology, each LED module , comprising any of the LED modules of claims 1 to 12 .14 . The arrangement of claim 13 , further comprising : a microcontroller unit coupled to the series of LED modules , wherein the microcontroller and the series of LED modules are arranged in daisy chain network topology .15 . A method of controlling communications in a light-emitting diode (LED) module arranged in a daisy chain network topology, the LED module configured to communicate using a differential signaling, the method comprising : testing a differential signaling connection of the LED module ; determining a connection failure in a differential connection used for differential signaling; and switching from communicating using differential signaling to communicating using single-ended signaling .

16. The method of claim 15 , wherein the differential signaling connection comprises a pair of wires , wherein determining the connection failure testing each wire of the pair of wires of the differential signaling connection .17 . The method of claim 16 , wherein determining a connection failure comprises determining a connection failure a single wire of the differential signaling connection .18 . The method of claim 17 , wherein determining a connection failure in a single wire of the differential signaling connection comprises determining an open fault the single wire .19 . The method of claim 17 , wherein determining a connection failure in a single wire of the differential signaling connection comprises determining a short fault in the single wire .20 . The method of any of claims 15 to 19 , wherein the LED module comprises a receiver for receiving communications through the differential signaling connection .

Images