CN201563264U

CN201563264U - Long-distance series connected LED (Light Emitting Diode) lamp communication system

Info

Publication number: CN201563264U
Application number: CN2009202104777U
Authority: CN
Inventors: 黄文君
Original assignee: SHANGHAI NAINUO TRADING CO Ltd
Current assignee: SHANGHAI NAINUO TRADING CO Ltd
Priority date: 2009-09-29
Filing date: 2009-09-29
Publication date: 2010-08-25
Anticipated expiration: 2019-09-29

Abstract

The utility model relates to a long-distance series connected LED (Light Emitting Diode) lamp communication system comprising a main node and a plurality of slave nodes, wherein the main node and the slave nodes are sequentially connected in series through signal lines, and the main node comprises a main controller and an output differential unit; the output differential unit of the main node receives a logic level signal sent by the main controller, and converts the logic level signal into a differential level signal and then sends the different level signal to an input differential unit of the slave node connected in series with the main node; and the input differential unit of each slave node converts the differential signal received into a logic level signal and then sends the logic level signal to a slave controller of the slave node, and the output differential unit receives the logic level signal sent from the slave controller, converts the logic differential level signal into the logic level signal and sends the logic level signal to the input different unit of the next slave node connected in series with the slave node. The long-distance series connected LED lamp communication system makes transmission in differential level signals, thereby greatly increasing the communication distance.

Description

Long apart from series LED lamp communication system

Technical field

The utility model relates to the LED lamp communication technology.

Background technology

In recent years, can realize that the led light source of full-color variation had replaced neon light substantially, become the main product of landscape light in city.At present, the LED landscape lighting control system on the market mainly contains following two types:

1.RS485 parallel control system:

The built-in a slice single-chip microcomputer of each LED light fixture is controlled and is connected on the RS485 bus, by a controller each single-chip microcomputer on the RS485 bus is controlled.The advantage of this control mode is that the RS485 technology maturation realizes simple, and command range is long, and shortcoming is: 1) this control mode need be set the address to each light fixture; 2) RS485 design bus in parallel adopts hand-in-hand bus topolopy, and modal hub-and-spoke configuration can produce reflected signal on the LED engineering, thereby has limited the pixel quantity of LED system; 3) number of nodes is few.According to the RS485 standard, its standard drive node number is 32, though some chip node number can reach 256, this obviously can't satisfy the demand of pixel quantity LED project up to ten thousand; 4) damage of a node can cause the paralysis of whole bus, the comparison difficulty of fixing a breakdown.

2. serial SPI control system:

Its uses and to include offset buffer, and the chip of data latching function by the mode of similar shift LD, joins end to end each LED pixel, deposits after receiving a byte data, sends the data of a byte then downwards.The advantage of this control mode is: 1) number of nodes is big.Generally can reach number of nodes more than 1000 as DM413 or this class chip of LPD6803; 2) do not have the constraint of address, installation and maintenance is fairly simple, is fit to very much the use of large-scale tv screen.But this control mode also has some shortcomings: 1) communication distance is short.This control mode belongs to single-ended signal and transmits, and has altogether noise and can not suppress problem such as common mode disturbances, makes two contacts not surpass 5～10 meters, limit its range of application greatly; 2) outlet is more.Because most of chips use the SPI mode, this just needs 3 control lines (clock, data, latch signal) and data ground wire at least, will make design difficulty increasings such as waterproof and dustproof like this; 3) standard can't be unified, because this class number of chips is numerous on the market, the application layer standard is also unified, so cause the various product can't be compatible.

Summary of the invention

Technical problem to be solved in the utility model is to provide a kind of length of telecommunication that realizes apart from series LED lamp communication system.

The technical scheme that the utility model adopted is: a kind of length is apart from series LED lamp communication system, comprise a host node and a plurality of from node, host node and a plurality ofly connect successively by holding wire from node, wherein, host node comprises master controller, respectively comprise slave controller and LED lamp from node, slave controller links to each other with the LED lamp; Be characterized in that host node also comprises an output difference unit, respectively also comprise an input difference unit and an output difference unit from node; The output difference unit of host node receives the logic level signal that sends of master controller, and sends to the input difference unit from node that is series at this host node after this logic level signal is converted to the differential level signal; Send to this slave controller after respectively with the differential level conversion of signals that receives being logic level signal from node from the input difference unit of node, the output difference unit receives the logic level signal that slave controller sends, and this logic level signal is converted to send to behind the differential level signal is series at this next input difference unit from node from node; Holding wire is a twisted-pair feeder.

The utlity model has following advantage:

1. the utility model adopts cascaded structure, need not to carry out geocoding, has reduced the difficulty of LED installation and maintenance.

2. the utility model is provided with difference unit at host node with from node, transmit by logic level signal being converted to the differential level signal, can suppress common ground noise and common mode disturbances, thereby increase communication distance greatly, and improve the reliability of communication.

3. adopt twisted-pair feeder as holding wire, reduced the data wire quantity of system.

4. compatible good.Because core of the present utility model is a hardware configuration, thereby is applicable to most of communication protocols in the market.

5. because the software application that data are deposited can make LED system pixel quantity increase greatly, saved traditional cabling requirement.

Description of drawings

Fig. 1 is a theory diagram of the present utility model.

Fig. 2 and Fig. 3 are respectively the schematic diagram of a kind of execution mode of input difference of the present utility model unit and output difference unit.

Embodiment

Below in conjunction with accompanying drawing the utility model is made and to be further specified.

As shown in Figure 1, length of the present utility model comprises a host node 1 and a plurality of from node 2 apart from series LED lamp communication system, host node 1 and a plurality ofly connect successively by holding wire 3 from node 2.Wherein, host node 1 comprises a master controller 11 and an output difference unit 13, respectively comprises slave controller 21, an input difference unit 22 and an output difference unit 23 and a LED lamp 24 from node 2.Slave controller 21 links to each other with LED lamp 24,

The output difference unit 13 of host node 1 receives the logic level signal that sends of master controllers 11, and sends to the input difference unit 22 from node that is series at this host node after this logic level signal is converted to the differential electrical ordinary mail.Send to this slave controller 21 after respectively with the differential level conversion of signals that receives being logic level signal from node from the input difference unit 22 of node 2, output difference unit 23 receives the logic level signal that slave controllers 21 send, and this logic level signal is converted to send to behind the differential electrical ordinary mail is series at this next input difference unit 22 from node from node.Holding wire 3 is a twisted-pair feeder.

Only schematically show three among Fig. 1 from node 2, in actual applications, can increase according to demand from the quantity of node.Because the utility model is provided with difference unit at host node with from node, after logic level signal being converted to the differential level signal, utilize twisted-pair feeder to transmit, can suppress common ground noise and common mode disturbances, thereby make the utility model can realize telecommunication.Under laboratory condition, the communication distance between two nodes of the present utility model can reach about 2000 meters, and in the LED engineering time, under the requirement of satisfying communication reliability, the communication distance between two nodes of the present utility model also can reach 800 meters.

Difference unit of the present utility model can adopt discharge circuit, also can adopt existing communication chip, for example MAX13085.Fig. 2 shows the circuit diagram that difference input unit of the present utility model adopts discharge circuit, among the figure, be output as VOUT+ from the logic level signal of slave controller through the conversion of amplifier, VOUT-, voltage difference between VOUT+ and the VOUT-is+2～+ logic state of 6V interval scale, for-6～-2V interval scale another one logic state, thus realize the conversion of logic level signal to the differential level signal.Fig. 3 shows an embodiment of difference output unit of the present utility model, and among the figure, differential level input signal RA, RB through voltage ratio produce the logic level that outputs to slave controller.

Master controller of the present utility model and slave controller all can adopt MCU, ARM or FPGA.Can make MCU realize the function of buffer and data latching by software.Realize that with software the method that latchs is roughly as follows: step 1, distribute and deposit the space and latch the space.Wherein, deposit the arrangement architecture that FIFO is used in the space, the degree of depth of FIFO is by the pixel figure place decision of LED.Step 2 when MCU receives 1 byte data, will deposit that data move 1 byte to afterbody in the space, and new data are deposited in deposits the space stem, and the data of afterbody are sent to next node; When receiving latch signal, deposit in and latch the space and carry out the PWM modulation depositing all data in the space, send latch signal to next node, and will deposit clear space.

Claims

1. one kind long apart from series LED lamp communication system, comprise a host node and a plurality of from node, described host node and described a plurality ofly connect successively by holding wire from node, wherein, host node comprises master controller, respectively comprises slave controller and LED lamp from node, and described slave controller links to each other with described LED lamp, it is characterized in that

Described host node also comprise one output difference unit, each described from node also comprise an input difference unit and one output difference unit;

The output difference unit of host node receives the logic level signal that sends of master controller, and sends to the input difference unit from node that is series at this host node after this logic level signal is converted to the differential level signal;

Each described input difference unit from node is to send to this slave controller from node behind the logic level signal with the differential level conversion of signals that receives, the output difference unit receives the logic level signal that slave controller sends, and this logic level signal is converted to send to behind the differential level signal is series at this next input difference unit from node from node;

Described holding wire is a twisted-pair feeder.

2. LED lamp communication system as claimed in claim 1 is characterized in that described master controller and described slave controller are MCU.