JPH02104035A - Optical communication equipment - Google Patents

Abstract

PURPOSE:To attain optical communication without adding any special constitution to an information processing unit side by obtaining a drive power for an optical communication equipment from a transmission electric signal line from the information processing unit directly. CONSTITUTION:An electric signal 44 received by a receiver circuit 3a enters a modulation circuit 38, in which pulse width modulation is applied to the input electric signal synchronously with the front ridge of a clock signal 47 from a clock circuit 39 to form a pulse width modulation signal 45. The signal is inputted to a drive circuit 4, a light emitting element 5 is lighted and the light is sent to a light receiving element of an opposite equipment via a connector 8 and an optical fiber cable 10a. A + or -V2 power supply is fed to a receiver circuit 3a and a driver circuit 3b of an interface circuit 3, and a +V1 power supply is fed to a modulation circuit 38 of a transmission circuit, a drive circuit 4 including a clock signal circuit 39 and the light emitting element 5, an amplifier circuit 6 including the light receiving element 7 of the reception circuit and a demodulation circuit 40.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to optical communication equipment connected between an optical communication medium and an information processing device.

[Prior Art] In recent years, in place of the conventional telecommunication system that mainly uses metal conductor cables, optical communication systems have been used that connect devices with each other using optical fiber cables and transmit information using optical signals. Examples are increasing. This is because it has advantages such as being capable of large-capacity communication and being less affected by electromagnetic noise. In particular, it has been widely adopted in the fields of specific line network communication and public line network communication.

Furthermore, recently, the field of information transmission between individual information processing devices with a relatively small amount of information has been developed, such as between electronic devices such as combinations, LANs and automatic control devices, LAN nodes and terminal devices, or host computers and terminal computers. It is being used for communication and as a signal transmission means within each of these devices.

However, when adopting optical communication for signal transmission between devices or within devices, it is necessary to separately prepare optical communication equipment required for dedicated optical communication in place of the conventional telecommunication interface. It won't happen.

In order to configure this optical communication device, an electric-to-optical conversion circuit driving section for driving an electric-to-optical conversion circuit in response to an electric signal from a processing device, an electric-to-optical conversion circuit (such as a light emitting element), A photo-electrical conversion circuit (light receiving element), an amplifier circuit for amplifying the signal from the circuit, etc. are required, and a drive power source for operating each of the above configurations is also required.

In addition, since each of these dedicated configurations is required, it has been impossible to use existing telecommunication system equipment as is to perform optical communication without adding special configurations or power supply equipment.

If you absolutely want to use existing equipment for optical communication, connect an optical communication adapter equipment that is equipped with a separate power supply equipment to obtain the necessary power from a dedicated commercial power supply, and then connect an optical fiber cable, etc. had to be connected to.

The configuration of such a conventional optical communication adapter device is
As shown in the figure.

In FIG. 4, 1 is optical communication equipment, 8.9 is an optical communication connector section, 10a and 10b are optical communication fiber cables,
14 is a power supply unit, 15 is an AC adapter, 16 is a plug, 2
0 is an information processing device.

In the case of bidirectional optical communication, the information transmission electrical signal S1 from the information processing device 2o is sent to the light emitting element drive circuit 4 via the electrical connection connector 2 and the receiver circuit 3a of the interface circuit 3, and the information is transmitted by the light emitting element 5. Transmission electrical signal S1
The signal is converted into an optical signal corresponding to , and sent out to the optical fiber cable 10a via the optical communication connector section 8, and transmitted to the light receiving element of the destination electronic device.

On the other hand, from the light emitting element of the other party's device to the optical fiber cable 1
The optical signal transmitted via 0b is received by the light receiving element 7 via the optical communication connector section 9, converted into a corresponding electric signal there, and amplified by the amplifier circuit 6, and then sent to the interface section 3. The signal is sent as a received signal to the signal line S2 of the information processing device 20 via the driver circuit 3b and the electrical connection connector 2.

In transmitting and receiving such signals, an electric-to-optical converter including a light-emitting element driving circuit 4 and a light-emitting element 5, an optical-to-electrical converter including an amplifier circuit 6 and a light-receiving element 7, and an interface circuit 3
The power required to drive the receiver circuit 3a and driver circuit 3b is all supplied from the power supply section 14.

Power is supplied to the power supply section 14 by converting a commercial AC power supply into DC power supply using an AC adapter (AC-DC converter) 15 and supplying it to the power supply receptor 17 of the power supply section 14 of the optical communication equipment via a plug 16. This is done by connecting. Alternatively, if the information processing device 20 is supplied with a dedicated power supply line P and the plug 16 from the AC adapter 15 is not inserted, the information processing device 2
It was configured to receive the necessary power from the power supply line from 0.

Then, the voltage of this power supply line is converted, and the power supply unit 1
A power of 10 V was output to the first terminal of the power supply 4, and ±V power was generated and supplied via a filter circuit consisting of a built-in inductor L and capacitors C4 and C5, and a DC-DC converter 18.

+V and electric power are supplied to the light emitting element 5, the light receiving element 7, and the drive circuit 4 that drives the light emitting element 5, and also to the amplifier circuit 6 that amplifies the electrical signal from the light receiving element 7. The ±v2v power is supplied to the receiver circuit 3a and driver circuit 3b of the interface circuit 3.

As a signal modulation/demodulation method during electrical-to-optical conversion and optical-to-electrical conversion, a direct luminance modulation/demodulation method with a relatively simple circuit configuration is adopted.

For example, in this direct brightness modulation and demodulation method, as shown in FIG.
The drive circuit 4 causes the light emitting element 5 to emit light so that the pulse duty time of the input electric signal directly corresponds to the light emitting time of the light emitting element 5. Also, during reception, the light receiving element 7
The received optical signal is converted here into an electrical signal with a pulse duty time corresponding to the light reception duty time, amplified by the amplifier circuit 6, and then sent to the information processing device 20 via the driver circuit 3b. .

[Problems to be Solved by the Invention] As described above, conventional optical communication equipment has been constructed using an electrical-to-optical conversion circuit consisting of an interface circuit 3, a drive circuit 4, and a light emitting element 5, and an amplifier circuit 6 and a light receiving element 7. All the power necessary to drive the optical-to-electrical conversion circuit and the like had to be separately procured from outside via a specially provided power supply device.

That is, it was necessary to output special driving power from within the information processing device 20 or to separately procure a configuration for obtaining a DC power source for driving the device from a commercial AC power source.

As a result, conventionally, it has been necessary to configure the information processing device 20 with a special optical communication configuration, or to provide a separate AC power terminal and a dedicated AC-DC converter, etc. This has the disadvantage of increasing the cost of optical communication equipment as a whole and making the equipment larger.

In addition, since conventional optical communication equipment uses a direct brightness modulation/demodulation method as a signal modulation/demodulation method, the light emitting element, which consumes the most power in optical communication equipment, is
Alternatively, it is necessary to continue emitting light during the low pulse duty time.

For this reason, power ranging from several hundred mW to several W was consumed. This reduction in power consumption was also an issue that needed improvement.

[Means for Solving the Problems] The present invention has been made for the purpose of solving the above-mentioned problems, and includes the following configurations in order to solve the above-mentioned problems.

That is, a first converting means inputs an electrical signal from an information processing device, pulse-width modulates the electrical signal, converts it to an optical communication medium as a corresponding optical signal, and outputs the pulse-width modulated light from the optical communication medium. a second converting means that inputs a signal, demodulates the signal, converts it as a corresponding electrical signal, and outputs it to the information processing device; and a second converting device for driving the first converting device and the second converting device based on the electrical signal from the information processing device. and power generation means for generating power.

[Function] With the above configuration, power for driving optical communication equipment can be obtained directly from the transmission electric signal line from the information processing device, and optical communication can be performed without adding any special configuration to the information processing device. can be made possible.

[Example] Hereinafter, an example according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of an embodiment according to the present invention. In FIG. 1, the same components as in FIG. 4 are given the same numbers,
Detailed explanation will be omitted.

The transmitting circuit is the receiver circuit 3 of the interface circuit 3.
a, a modulation circuit 38 that modulates the input electrical signal 44 into a pulse width in FIG.
Consists of. The receiving side circuit also includes a light receiving element 7 that receives the transmitted modulated optical signal and converts it into an electrical signal, an amplifying circuit 6 that amplifies the signal from the light receiving element 7, and this amplifying circuit 6.
a demodulation circuit 40 that demodulates the modulated received electrical signal 46;
and a driver circuit 3b of the interface circuit 3.

Further, the signal S1 outputted from the signal output driver circuit (not shown) of the information processing device 2o is also input to the stabilized power supply circuit 41, and the signal S1 is determined based on the signal S1 required for the device. ±■
3 each power is generated. Note that in the drawings, signal circuit lines are shown as thin lines and power circuit lines are shown as thick lines for easy explanation.

The operation of this embodiment with the above configuration is shown in FIG.
CB) will be explained below with reference to the timing chart.

A transmission signal S1 output from a driver circuit (not shown) built in the information processing device 20 is sent to the receiver circuit 3a of the interface circuit 3 via the connector 2.
is output to. At the same time, the transmission signal Sl is also input to the stabilized power supply circuit 41.

First, to explain the transmitting side circuit, the receiver circuit 3a
The electrical signal 44 received by the clock enters the modulation circuit 38, where it applies pulse width modulation to the input electrical signal in synchronization with the leading edge of the clock signal 47 sent from the clock circuit 39 to the modulation circuit 38. A width modulated signal 45 is formed. This modulated signal is input to the drive/video path 4, and is emitted as a corresponding optical signal by the light emitting element 5, and is sent to the light receiving element of the other device via the connector 8 and the optical fiber cable 10a.

This input signal 44. Modulation signal 45 and clock signal 47
The timing chart of FIG. 2(A) is shown in FIG.
The light emitting element 5 emits light only while the modulation signal 45 in A) is on.

As described above, the driving method of the light emitting element 5, which consumes the most power in optical signal equipment, has been improved from the conventional direct brightness modulation method to the pulse width modulation method, and the light emission time of the light emitting element 5 has been improved by several tens of seconds compared to the conventional method. It has been reduced to a fraction of a minute to several hundred times. Second
As shown in Figure (A), the input electrical signal is input to the modulation circuit 38, and the input electrical signal 44 is inputted to the modulation circuit 38 at the rising timing of the clock signal 47 sent from the clock signal circuit 39.
Detects “old GH” and “Low” of input electric signal 44
At the rising edge of , the signal for two periods of the clock signal becomes,
Further, when the input electric signal 44 falls, it is modulated into a signal corresponding to one cycle of the clock signal, and this modulated signal 45 is transmitted to the drive circuit 4.

The light emitting element 5 driven in accordance with this modulation signal 45 is
Compared to the conventional method where the input electric signal 44 is directly driven for the entire time, the light emission time is several tens of minutes to several hundred minutes.
can be reduced to

On the other hand, as shown in FIG. 1, the optical signal sent from the other party's device via the optical fiber cable lOb is a modulated signal modulated in the same manner as described above. In the receiving circuit,
an optical fiber cable 10b from the light emitting element of the other party's device;
An optical signal sent via the connector 9 and modulated and transmitted in the same manner as in the above transmission is received by the light receiving element 7, where it is optical-to-electrically converted. This converted electrical signal is amplified by the amplifier circuit 6 and inputted to the demodulation circuit 40 as a modulation signal 46. The demodulation circuit 40 compares the timer output of the built-in timer and determines whether the signal is “High” or “Lo”.
w" is determined and demodulated as a demodulated output signal 48.

The demodulated electrical signal 48 is sent to the information processing device 20 via the driver circuit 3b of the interface circuit 3 and the connector 2 as a signal line S2.

This received modulated signal 46. A timing chart between the demodulated output signals 48 is shown in FIG. 2(B).

The output waveform from the timer circuit built into the illustrated demodulation circuit 40 is not smaller than one cycle of the clock signal 47, and is not smaller than 2 cycles.
It is a signal that is less than the period, and is activated at the rising edge of the modulation signal 46, and when the output waveform from the timer is deactivated, the modulation signal 46 is activated.
The rise or fall of the demodulated output signal 48 is determined by whether it is "old GH" or "Low".

As a result of the demodulation as described above, the light emission time of each light emitting element 5 can be minimized, and power consumption can be reduced.

Additionally, since the pulse widths of the rising and falling edges of the original signal are made different during modulation, malfunctions may occur if there is an influence such as noise on the way, or if the input signal is minute. Even if the error occurs, the error can be recovered quickly and its impact can be minimized.

Note that the modulation/demodulation method of this embodiment is not limited to the above example, and may be applied to control signals such as when the information processing device starts up (when the modem device in the device starts up, and the DTR signal rises, etc.). By creating a configuration that outputs a distinguishable signal such as a carrier signal when
It is also possible to notify the other party of the necessary device status.

Next, a means for supplying power for driving such a transmitting/receiving circuit will be explained with reference to FIG.

FIG. 3 is a detailed diagram of the stabilized power supply circuit 41 of the device of this embodiment, and D1. D2 is a rectifier diode, CI, C2
is a smoothing capacitor, 12 is a voltage regulator, 13 is D
C-DC converter, D3. D4 is a protection diode,
C3 is a filter capacitor.

The electrical signal input from the signal line S1 from the information processing device 20 through the electrical connection connector 2 has a "+" potential, "
-" It is rectified by the rectifier diodes DI and D2 according to the potential, and the ripple is removed and smoothed by the smoothing capacitors CI and C2. After that, the ±v2 power supply is DC-D
The signal is stabilized by the action of the C converter 13 and output. This ±V2 power is supplied to the receiver circuit 3a and driver circuit 3b of the interface circuit 3.

At the same time, the "+" level input is smoothed by removing ripples by the smoothing capacitor C1, then stabilized by the voltage regulator 12, and +vl power is supplied.
The Vl power is supplied to the drive circuit 4 including the modulation circuit 38, the clock signal circuit 39, and the light emitting element 5 of the transmitting circuit, and the amplifier circuit 6 and the demodulating circuit 40 including the light receiving element 7 of the receiving circuit.

Here, the power supplied from the stabilized power supply circuit 41 is limited by the supply current of the transmission signal output driver circuit in the connected information processing device 20. In addition, control output driver circuits other than the transmission output driver circuit can also be used as power8. For example, if the interface specification is R3-232C specification, RTS, DT
R signal etc. can be used.

Further, the voltage regulator 12 and the DC-DC converter 13 need to be formed with low power consumption types as much as possible, and it is preferable to use MOS-FET type ones, and the other circuit parts in this embodiment have a CMOS gate configuration. It is desirable to reduce power consumption. Note that if more driving power is required for the light emitting element 5, the voltage regulator 12 may be a highly efficient DC-DC converter.

In the above explanation, it was particularly effective when transmitting and receiving character code data such as ASCII, but when transmitting image data, etc., for example, it is necessary to keep the LOW level (or old GH level) for a long time. Continuous cases are also possible.

In such a case, there is a possibility that the "-" power (-V2) will be insufficient. In this case, there may be cases where level conversion cannot be performed sufficiently, so if there is such transmission data, not only the "+" power required when the signal line is at the "+" level, but also the "+" In addition to electricity,
It is sufficient to provide a circuit system such as a converter to obtain the required "-" power, thereby making it possible to deal with all signal line conditions.

In this case, the "-" power supply is simply used to maintain the level of the output signal to the information processing device 20, and consumes only a small amount of power.
It is sufficient to receive this power from the output signal line from 0.

In this way, the “+” of the output signal line from the information processing device 20
By generating the necessary power from both the level and the "-" level or from the circuit system described above, optical transmission can be performed reliably and accurately regardless of the content of the transmitted and received data.

Further, by changing the power for driving the light emitting element 5 and the like to a voltage driving method and using a constant current driving method, power consumption can be further reduced.

There is no particular restriction on the data transmission start timing of the information processing device 20, and if the processing speed of the information processing device 20 is fast, communication may be started as soon as the data communication becomes possible. If the time until the information processing device 20 starts transmitting data is short, the above-mentioned voltage regulator 12
If the input-output potential difference is large, there is a risk that the first transmission data from the information processing device 20 will be lost. To prevent this, in such a case, the voltage regulator 12
This reduces the potential difference between the input voltage and the output voltage, thereby shortening the time it takes for the device of this embodiment to start operating. Alternatively, it is also possible to generate the necessary power from "-" until the start of operation using a converter circuit or the like.

As described above, according to this embodiment, the pulse width modulation/demodulation method is adopted as the signal driving method to reduce the driving power of the light emitting element 5, and the driving power of the optical communication equipment is inputted to the optical communication equipment. Since the configuration allows the electrical signals to be obtained from the electrical signals transmitted by the It has become possible to perform optical communication with devices equipped with this configuration.

In this way, cost reduction, miniaturization, and power saving of optical communication equipment have been achieved, and the effect of contributing to the industry is extremely large.

[Effects and Effects of the Invention] As explained above, according to the present invention, there is no need to make any changes or add any special configuration to an existing device having an electrical communication control configuration via a metal conductor. This makes it possible to perform optical communication without any interference.

Furthermore, it is possible to provide a highly reliable device that consumes less power and can minimize transmission errors.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of an optical communication device according to an embodiment of the present invention, Fig. 2 (A) is a timing chart showing modulation processing of this embodiment, and Fig. 2 (B) is a demodulation processing of this embodiment. FIG. 3 is a detailed circuit diagram of the stabilized power supply circuit diagram of this embodiment. FIG. 4 is a circuit diagram of a conventional optical communication device. FIG. Timing chart showing the timing. FIG. 5(B) is a timing chart showing the received electrical signal with respect to the conventional light receiving timing. In the figure, l... Optical communication equipment, 2... Electrical connection connector, 3... Interface circuit, 3a... Receiver circuit, 3b... Driver circuit, 4... Drive circuit, 5
... Light emitting element, 6... Amplifying circuit, 7... Light receiving element, 8.9... Optical communication connector section, 10a, 10b...
・Optical communication fiber cable, 12...Regulator, 13゜18...DC-DC converter, 14.41
... Stabilized power supply circuit, 15 ... AC adapter, 16
... Plug, 20 ... Information processing device, 38 ... Modulation circuit, 39 ... Clock signal circuit, 40 ... Demodulation circuit. Patent Applicant: Tokyo Totoku Electric Wire Co., Ltd. Japan Chikunat Co., Ltd. Representative Patent Attorney Yasunori Otsuka (1 other person)

Claims (2)

[Claims] (1) An optical communication device connected between an optical communication medium and an information processing device, which inputs an electrical signal from the information processing device, pulse-width modulates it, and converts it into a corresponding optical signal to the optical communication medium. a first converting means for converting and outputting the pulse width modulated optical signal from the optical communication medium, and a second converting means for inputting the pulse width modulated optical signal from the optical communication medium, demodulating it, and converting and outputting it as a corresponding electric signal to the information processing device. An optical communication device, comprising: a means for generating power for driving the device from an electric signal from the information processing device. (2) The first converting means outputs a corresponding optical signal only when the polarity of the input electrical signal is reversed, and the second converting means reverses the polarity of the output electrical signal corresponding to each input of the optical signal. 2. The optical communication device according to claim 1, characterized by: