CN203883846U - Data photoelectric conversion device - Google Patents
Data photoelectric conversion device Download PDFInfo
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- CN203883846U CN203883846U CN201420284039.6U CN201420284039U CN203883846U CN 203883846 U CN203883846 U CN 203883846U CN 201420284039 U CN201420284039 U CN 201420284039U CN 203883846 U CN203883846 U CN 203883846U
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Abstract
The utility model relates to a data photoelectric conversion device including an optical fiber transmit-receive module, a signal logic processing circuit and an interface circuit. The optical fiber transmit-receive module is in two-way communication with the signal logical processing circuit. The signal logic processing circuit is in two-way communication with the interface circuit. The data photoelectric conversion device can realize photoelectric conversion of three different interfaces: RS485, RS422 and RS232, thereby meeting different demands of users. With the adoption of two identical conversion modules, data communication between different standard interfaces on a data link can be realized, and thus some special demands are satisfied. The data photoelectric conversion device is realized by means of a hardware circuit, uses the ultra-low-speed optical communication technology to directly perform base-band transmission of data signals, and thus a modulation-demodulation circuit in low-Baud-rate transmission in a conventional optical communication is omitted. The data photoelectric conversion device has a simple hardware circuit, and has the advantages of high reliability and low cost.
Description
Technical field
The utility model relates to opto-electronic conversion and the networking of industrial circle RS232, RS485, RS422 communication, particularly a kind of data light electrical switching device.
Background technology
In industrial circle, communication mode mainly contains three kinds of modes, is respectively cable communication, radio communication and optical fiber communication.Optical fiber communication has the plurality of advantages such as antijamming capability is strong, capacity is large, cost is low, communication distance is far away, and along with China's copper matting enters implementation, the application of optical fiber communication is more and more extensive.
RS232, RS422 and RS485, as a kind of electrical code of multipoint data transmission, have become three kinds of conventional in the industry data transmission standards, and the equipment such as the local area network (LAN) of many different industrial circles, intelligent building all have this class interface.These three kinds of interfaces respectively have feature, and wherein RS232 and RS422 interface can provide full duplex asynchronous data communication, but RS232 communication distance is shorter, and have the deficiency of poor anti jamming capability, and RS422 communication needs 4 core cables, has the shortcoming that cost is higher.RS485 communication only needs 2 core cables, but semiduplex asynchronous data communication can only be provided.RS485 and RS422 interface communication distance are higher than RS232, but when traffic rate is higher, its communication distance only can reach hundreds of rice, and having relatively high expectations to telecommunication cable.In addition the network topology structure of these three kinds of interfaces is not all supported ring-like or hub-and-spoke configuration, makes comparatively inconvenience of networking between equipment, and system cost is higher.
In sum, because the feature of distinct interface is not quite similar, product interface is difficult to unified.The scheme that solves problems has two: the one, adopt unified interface standard, from the current state of the art, technical grade Ethernet will be a very important selection, the 2nd, design a kind of universal transducer, for the equipment network of distinct interface provides a solution.The former has good development prospect, is difficult in a short time realize, and cannot be suitable for the deficiency of existing device but exist, and the latter has advantages of lower, the convenient enforcement of cost.
Utility model content
The purpose of this utility model is to overcome the defect that prior art exists, and provides the opto-electronic conversion of a kind of RS485 of realization, RS422 and tri-kinds of distinct interfaces of RS232 to meet the data light electrical switching device of the demand that user is different.
The technical scheme that realizes the utility model object is: a kind of data light electrical switching device, comprises optical fiber receiver-transmitter module, signal logic treatment circuit and interface circuit; Described optical fiber receiver-transmitter module and signal logic treatment circuit both-way communication; Described signal logic treatment circuit and interface circuit both-way communication; Described optical fiber receiver-transmitter module comprises mirror current source, semiconductor laser LD, photodetector PD and automatic power control circuitry; The two ends of described semiconductor laser LD and photodetector PD connect input and the output of mirror current source respectively; The input of described automatic power control circuitry is connected to the output of mirror current source by adjustable resistance R18, the input of the output termination mirror current source of automatic power control circuitry;
Described signal logic treatment circuit comprises logic chip U3A, the U3D of series connection successively and the first branch road of U3C, and the logic chip U7C of series connection and the second branch road of U3B;
Described interface circuit comprises RS232 interface circuit, RS422 interface circuit and RS485 interface circuit; The data receiver of the data receiver of described RS422 interface circuit and RS485 interface circuit is all connected to the transmitting terminal of optical fiber receiver-transmitter module by the first branch road; The data receiver of described RS232 interface circuit is connected to the transmitting terminal of optical fiber receiver-transmitter module by U3A, the data output end of the data output end of RS232 interface circuit and RS485 interface circuit is connected to the receiving terminal of optical fiber receiver-transmitter module by logic chip U7C; The sending/receiving control end of described RS485 interface circuit is connected to the receiving terminal of optical fiber receiver-transmitter module by second to branch road.
Described in technique scheme, RS232 interface circuit comprises charge pump circuit and data transaction passage; Described charge pump circuit is comprised of MAX232 chip U2, capacitor C 1, C2, C3 and C4, for provide+12V of RS232 serial ports power supply and-12V power supply; Described data transaction passage comprises two groups of data channel for mutually changing between TTL/CMOS data and RS232 data.
Described in technique scheme, RS422 interface circuit comprises differential data transceiver U4; The differential signal end of the sending/receiving of described differential data transceiver U4 connects RS422 serial ports by binding post, send differential signal end by diode D2 in parallel and the rear ground connection of resistance R 5, receive differential signal end by diode D1 ground connection, and by connect+5V of resistance R 6 power supply, the receiver output of differential data transceiver U4 is connected to the transmitting terminal of optical fiber receiver-transmitter module by the first branch road.
Described in technique scheme, RS485 interface circuit comprises differential data transceiver U6; The differential signal end of the sending/receiving of described differential data transceiver U6 connects RS485 serial ports by binding post, send differential signal end by diode D3 in parallel and the rear ground connection of resistance R 15, receive differential signal end by diode D4 ground connection, and by connect+5V of resistance R 16 power supply, the receiver output of differential data transceiver U6 is connected to the transmitting terminal of optical fiber receiver-transmitter module by the first branch road.
Described in technique scheme, mirror current source is comprised of triode Q2, Q3 and Q4; The emitter of described triode Q2 and Q3 is connected to respectively the collector electrode of triode Q4 by resistance R 9 and R10.
Described in technique scheme, automatic power control circuitry comprises control chip U9; Described control chip U9 is CA3140.
Described in technique scheme, differential data transceiver U4 and differential data transceiver U6 are the 6LBC184 differential data transceiver with built-in transition noise protective device.
Described in technique scheme, logic chip U3A, U3D, U3C and U3B are TC4011; Described logic chip U7C is 74HC04.
Adopt after technique scheme, the utlity model has following positive effect:
(1) the utility model hardware circuit is succinct, reliable and stable, is useful in the severe occasion of environment, can realize the opto-electronic conversion of RS485, RS422 and tri-kinds of distinct interfaces of RS232 to meet the demand that user is different.Adopt two identical modular converters also can realize the data communication between various criterion interface in data link, to meet some specific demands.
(2) the utility model adopts logical circuit to realize the data transparencyization transmission of distinct interface standard, and any baud rate within the scope of can self adaptation 0-10M, can extensively meet user's requirement.
(3) the utility model adopts hardware circuit to realize, used Ultra-Low Speed optical communication technology directly to adopt baseband transmission to data-signal, omitted the modulation-demodulation circuit that traditional optical communication must adopt when low baud rate transmission, this device hardware circuit is succinct, there is reliability high, the advantage that cost is low.
(4) the utility model adopts modular construction, can meet the photoelectric converting function of the interface of varying number and standard, adopt this device networking can form bus-type, star-like and ring network topological structure, can coexist by real photoelectricity, expand the topological scope of network, overcome the deficiency that RS232, RS422 and RS485 interface can only be constructed bus-network.
(5) the utility model differential data transceiver U4 and differential data transceiver U6 are the 6LBC184 differential data transceiver with built-in transition noise protective device; significantly improved the reliability of supporting the transition noise on impedance data synchronous transmission cable, this reliability has surpassed most similar devices.Adopt sort circuit that direct-connected (not tape insulation transformer) data line interface cheaply can be provided reliably, without any need for outer member.
Accompanying drawing explanation
For content of the present utility model is more easily expressly understood, according to specific embodiment also by reference to the accompanying drawings, the utility model is described in further detail, wherein below
Fig. 1 is structured flowchart of the present utility model;
Fig. 2 is optical fiber receiver-transmitter module schematic diagram of the present utility model;
Fig. 3 is signal logic treatment circuit figure of the present utility model;
Fig. 4 is interface circuit figure of the present utility model;
Fig. 5 is that the transmitter of differential data transceiver of the present utility model drives menu;
Fig. 6 is the receiver menu of differential data transceiver of the present utility model;
Embodiment
(embodiment 1)
See Fig. 1 to Fig. 6, a kind of data light electrical switching device, comprises optical fiber receiver-transmitter module 1, signal logic treatment circuit 2 and interface circuit 3; Optical fiber receiver-transmitter module 1 and signal logic treatment circuit 2 both-way communications; Signal logic treatment circuit 2 and interface circuit 3 both-way communications;
See Fig. 2, optical fiber receiver-transmitter module 1 comprises mirror current source, semiconductor laser LD, photodetector PD and automatic power control circuitry; Mirror current source is comprised of triode Q2, Q3 and Q4; The emitter of triode Q2 and Q3 is connected to respectively the collector electrode of triode Q4 by resistance R 9 and R10; The two ends of semiconductor laser LD and photodetector PD connect input and the output of mirror current source respectively; The input of automatic power control circuitry is connected to the output of mirror current source by adjustable resistance R18, the input of the output termination mirror current source of automatic power control circuitry, and automatic power control circuitry comprises control chip U9; Control chip U9 is CA3140; Optical fiber receiver-transmitter module 1 mainly completes the mutual conversion of light signal and the signal of telecommunication, adopts the optical wavelength of 1310nm.Optical fiber receiver-transmitter module 1 adopts Ultra-Low Speed optical communication technology directly to adopt baseband transmission mode to data-signal, completes the mutual conversion of light signal and the signal of telecommunication.That the light emitting semiconductor device of optical fiber receiver-transmitter module 1 adopts is semiconductor laser LD.Semiconductor laser LD Emission Lasers, fast response time, luminous power is large, high directivity, optic spectrum line is narrower, is generally used in the optical communication system of large capacity, long distance.This device adopts the mode of baseband transmission directly the information that will transmit to be changed into current signal Semiconductor Lasers LD, it is the method for a kind of light intensity modulation (IM), omitted complicated light modulation demodulator circuit, made optical fiber receiver-transmitter module 1 simple circuit, improved stability and reduced cost.
In laser array, the light of exporting dorsad from semiconductor laser LD completes the electric current of the corresponding size of opto-electronic conversion output through photodetector PD.Thereby if the principle that this automated power is controlled is Output optical power be greater than rated value the bias current by FEEDBACK CONTROL semiconductor laser LD reduce drive current and make semiconductor laser LD output power-handling capability, thereby if luminous power be less than rated value the bias current by FEEDBACK CONTROL semiconductor laser LD increase drive current and make semiconductor laser LD recover power-handling capability, Output optical power that like this can basicly stable semiconductor laser LD.With semiconductor laser LD Output optical power, reduce to set forth the automatic control process of this circuit, semiconductor laser LD Output optical power reduces, the power output of light reduces dorsad, photodetector PD output current reduces, and U9 end of oppisite phase input voltage reduces, and control chip U9 output voltage rises, the base current of triode Q4 rises, triode Q3 collector bias current rises, and photodetector PD Output optical power rises, thereby it is constant to maintain light Output optical power.
See Fig. 3, signal logic treatment circuit 2 comprises logic chip U3A, the U3D of series connection successively and the first branch road of U3C, and the logic chip U7C of series connection and the second branch road of U3B; Logic chip U3A, U3D, U3C and U3B are TC4011; Logic chip U7C is 74HC04.
Signal logic treatment circuit 2 adopts logic chip TC4011 and 74HC04 to process the logical relation between each signal, avoids competition and conflict between signal.
(R0 & R1 & RS232_R2OUT), TXDI connects optical fiber receiver-transmitter module 1 transmitting terminal, and R0 connects RS422 data receiver, and R1 connects RS485 data receiver, and RS232_R2OUT connects RS232 data receiver.Notebook data photoelectric conversion device is supported RS232, RS422, tri-kinds of interfaces of RS485, but synchronization only has that wherein a certain interface is in communication, and other two kinds in idle condition.As RS485 when the communication RS232, RS422 be just in idle condition, and idle condition is state 1, and 1 carry out remaining unchanged with operation, so the state of TXDI optical fiber receiver-transmitter module 1 transmitting terminal is just identical with the state of RS485, the electricity that completes RS485 turns light.RXDO, DIO is connected respectively to the data output end of RS485, RS232, and RXDO is connected to the receiving terminal of optical fiber receiver-transmitter module 1.RE/DEO=RXDO, RE/DEO is connected to transmission, the reception control end of RS485, when RS485 transmission data are logical one, RS485 drives chip in accepting state, an electricity mouthful bus state is logical one, when RS485 transmission data are logical zero, RS485 drives chip in transmission state, and an electricity mouthful bus state is logical zero.
See Fig. 4, interface circuit 3 comprises RS232 interface circuit, RS422 interface circuit and RS485 interface circuit; The data receiver of the data receiver of RS422 interface circuit and RS485 interface circuit is all connected to the transmitting terminal of optical fiber receiver-transmitter module 1 by the first branch road; The data receiver of RS232 interface circuit is connected to the transmitting terminal of optical fiber receiver-transmitter module 1 by U3A, the data output end of the data output end of RS232 interface circuit and RS485 interface circuit is connected to the receiving terminal of optical fiber receiver-transmitter module 1 by logic chip U7C; The sending/receiving control end of RS485 interface circuit is connected to the receiving terminal of optical fiber receiver-transmitter module 1 by second to branch road.
RS232 interface circuit comprises charge pump circuit and data transaction passage; Charge pump circuit is comprised of MAX232 chip U2, capacitor C 1, C2, C3 and C4, for provide+12V of RS232 serial ports power supply and-12V power supply; Data transaction passage comprises two groups of data channel for mutually changing between TTL/CMOS data and RS232 data, wherein 13 pin (R1IN), 12 pin (R1OUT), 11 pin (T1IN), 14 pin (T1OUT) are the first data channel, 8 pin (R2IN), 9 pin (R2OUT), 10 pin (T2IN), 7 pin (T2OUT) are the second data channel, TTL/CMOS data convert RS-232 data to from T1OUT, T2OUT output from T1IN, T2IN input, and RS-232 data are exported from R1OUT, R2OUT from R1IN, R2IN input converts TTL/CMOS data to.
RS422 interface circuit comprises differential data transceiver U4; The differential signal end of the sending/receiving of differential data transceiver U4 connects RS422 serial ports by binding post, send differential signal end by diode D2 in parallel and the rear ground connection of resistance R 5, receive differential signal end by diode D1 ground connection, and by connect+5V of resistance R 6 power supply, the receiver output of differential data transceiver U4 is connected to the transmitting terminal of optical fiber receiver-transmitter module 1 by the first branch road.
RS485 interface circuit comprises differential data transceiver U6; The differential signal end of the sending/receiving of differential data transceiver U6 connects RS485 serial ports by binding post, send differential signal end by diode D3 in parallel and the rear ground connection of resistance R 15, receive differential signal end by diode D4 ground connection, and by connect+5V of resistance R 16 power supply, the receiver output of differential data transceiver U6 is connected to the transmitting terminal of optical fiber receiver-transmitter module 1 by the first branch road.Differential data transceiver U4 and differential data transceiver U6 are the 6LBC184 differential data transceiver with built-in transition noise protective device.
No. 1 pin R of 6LBC184 chip and No. 4 pin D ends are respectively the output of receiver and the input of driver; No. 2 pin/RE and No. 4 pin DE ends are respectively the Enable Pin that receives and send, and when/RE is logical zero, device is in accepting state; When DE is logical one, device is in transmission state; No. 6 pins and No. 7 pin side a and bs are respectively the differential signal end that receives and send, and when the level of A pin is during higher than B, the data that representative sends are logical one; When the level of A is held lower than B, the data that representative sends are logical zero.Fig. 5 is that 6LB184 transmitter drives menu, and Fig. 6 is 6LB184 receiver menu.
In Fig. 4, differential data transceiver U6, as the driving chip of RS485, because RS485 is semiduplex, needs control signal RE/DE0 to control transmission, the accepting state of differential data transceiver U6.Control signal RE/DE0 is provided by the signal logic treatment circuit 2 of data light electrical switching device.When this data light electrical switching device is used as RS422 opto-electronic conversion, because RS422 is full duplex, in Fig. 4-3, U4 drives chip as the reception of RS422, and differential data transceiver U6 drives chip as the transmission of RS422.
MAX232 chip is IC chip production, that comprise two-way reception and driver of MAXIM company, is applicable to various EIA-232C and communication interface V.28/V.24.MAX232 chip internal has a supply voltage converter, 5V voltage transformation can be become to the required positive and negative 10V voltage of RS-232C output level.So, adopt the serial communication system of this chip interface only to need single+5V power supply just passable.
Above-described specific embodiment; the purpose of this utility model, technical scheme and beneficial effect are further described; institute is understood that; the foregoing is only specific embodiment of the utility model; be not limited to the utility model; all within spirit of the present utility model and principle, any modification of making, be equal to replacement, improvement etc., within all should being included in protection range of the present utility model.
Claims (8)
1. a data light electrical switching device, comprises optical fiber receiver-transmitter module, signal logic treatment circuit and interface circuit; Described optical fiber receiver-transmitter module and signal logic treatment circuit both-way communication; Described signal logic treatment circuit and interface circuit both-way communication; It is characterized in that: described optical fiber receiver-transmitter module comprises mirror current source, semiconductor laser LD, photodetector PD and automatic power control circuitry; The two ends of described semiconductor laser LD and photodetector PD connect input and the output of mirror current source respectively; The input of described automatic power control circuitry is connected to the output of mirror current source by adjustable resistance R18, the input of the output termination mirror current source of automatic power control circuitry;
Described signal logic treatment circuit comprises logic chip U3A, the U3D of series connection successively and the first branch road of U3C, and the logic chip U7C of series connection and the second branch road of U3B;
Described interface circuit comprises RS232 interface circuit, RS422 interface circuit and RS485 interface circuit; The data receiver of the data receiver of described RS422 interface circuit and RS485 interface circuit is all connected to the transmitting terminal of optical fiber receiver-transmitter module by the first branch road; The data receiver of described RS232 interface circuit is connected to the transmitting terminal of optical fiber receiver-transmitter module by U3A, the data output end of the data output end of RS232 interface circuit and RS485 interface circuit is connected to the receiving terminal of optical fiber receiver-transmitter module by logic chip U7C; The sending/receiving control end of described RS485 interface circuit is connected to the receiving terminal of optical fiber receiver-transmitter module by second to branch road.
2. data light electrical switching device according to claim 1, is characterized in that: described RS232 interface circuit comprises charge pump circuit and data transaction passage; Described charge pump circuit is comprised of MAX232 chip U2, capacitor C 1, C2, C3 and C4, for provide+12V of RS232 serial ports power supply and-12V power supply; Described data transaction passage comprises two groups of data channel for mutually changing between TTL/CMOS data and RS232 data.
3. data light electrical switching device according to claim 1, is characterized in that: described RS422 interface circuit comprises differential data transceiver U4; The differential signal end of the sending/receiving of described differential data transceiver U4 connects RS422 serial ports by binding post, send differential signal end by diode D2 in parallel and the rear ground connection of resistance R 5, receive differential signal end by diode D1 ground connection, and by connect+5V of resistance R 6 power supply, the receiver output of differential data transceiver U4 is connected to the transmitting terminal of optical fiber receiver-transmitter module by the first branch road.
4. data light electrical switching device according to claim 1, is characterized in that: described RS485 interface circuit comprises differential data transceiver U6; The differential signal end of the sending/receiving of described differential data transceiver U6 connects RS485 serial ports by binding post, send differential signal end by diode D3 in parallel and the rear ground connection of resistance R 15, receive differential signal end by diode D4 ground connection, and by connect+5V of resistance R 16 power supply, the receiver output of differential data transceiver U6 is connected to the transmitting terminal of optical fiber receiver-transmitter module by the first branch road.
5. data light electrical switching device according to claim 1, is characterized in that: described mirror current source is comprised of triode Q2, Q3 and Q4; The emitter of described triode Q2 and Q3 is connected to respectively the collector electrode of triode Q4 by resistance R 9 and R10.
6. data light electrical switching device according to claim 1, is characterized in that: described automatic power control circuitry comprises control chip U9; Described control chip U9 is CA3140.
7. data light electrical switching device according to claim 3, is characterized in that: described differential data transceiver U4 and differential data transceiver U6 are the 6LBC184 differential data transceiver with built-in transition noise protective device.
8. data light electrical switching device according to claim 1, is characterized in that: described logic chip U3A, U3D, U3C and U3B are TC4011; Described logic chip U7C is 74HC04.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420284039.6U CN203883846U (en) | 2014-05-29 | 2014-05-29 | Data photoelectric conversion device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420284039.6U CN203883846U (en) | 2014-05-29 | 2014-05-29 | Data photoelectric conversion device |
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| CN203883846U true CN203883846U (en) | 2014-10-15 |
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| CN201420284039.6U Expired - Fee Related CN203883846U (en) | 2014-05-29 | 2014-05-29 | Data photoelectric conversion device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104270198A (en) * | 2014-05-29 | 2015-01-07 | 常州石广电子有限公司 | Data photoelectric conversion device |
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2014
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104270198A (en) * | 2014-05-29 | 2015-01-07 | 常州石广电子有限公司 | Data photoelectric conversion device |
| CN104270198B (en) * | 2014-05-29 | 2017-01-18 | 常州石广电子有限公司 | Data photoelectric conversion device |
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| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20141015 Termination date: 20170529 |
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| CF01 | Termination of patent right due to non-payment of annual fee |