JPH05167059A - Photoelectronic integrated circuit - Google Patents

Abstract

PURPOSE:To transmit, in series, a piece of data which has been transmitted in parallel by means of high-pin counts, to reduce the number of pins in a photoelectronic integrated circuit and to achieve a high-density mounting operation by a method wherein the piece of data between photoelectronic integrated circuits is transmitted by means of an optical signal. CONSTITUTION:A parallel signal which is output from a CPU 70 is converted into a serial signal by means of a parallel/serial conversion part 72. The serial signal is converted into light by means of a light-emitting element for an optical input/output mechanism in an E/O conversion part 74. The optical signal which has been emitted from the light-emitting element is passed through a fiber lens and reaches a reflecting plate. The optical signal which has hit the reflecting plate is reflected to a direction parallel to a printed-circuit board; it is passed through a light waveguide; it is transmitted to an O/E conversion part 80 in an optical input/output mechanism; a photodetector converts the received optical signal into an electric signal and transmits it to a serial/parallel conversion part 82. The serial/parallel conversion part 82 convertes a serial signal into a parallel signal and transmits it to a CPU 70.

Description

Detailed Description of the Invention

[0001]

The present invention relates to high-density mounting, and
The present invention relates to an optoelectronic integrated circuit suitable for high-speed data transmission with less waveform distortion.

[0002]

2. Description of the Related Art Conventionally, data transmission between LSIs has been performed by a copper pattern on a printed circuit board 5, as shown in the concept of FIG. Specifically, as shown in FIG. 13, each LS
By electrically connecting the lead 106d of I1d to the pad 3 or through hole for soldering the copper pattern, the electrical connection between the LSIs 1d is achieved.

As a patent application of this type, Japanese Patent Application No.
2-306121 and the like.

[0004]

However, recently, LSI
Since the number of pins is increasing and the copper pattern has a narrow pitch, it is becoming difficult to draw out the copper pattern.
The conventional technology is no longer able to handle this.

Further, when high-speed data is transmitted by the copper pattern, there is a problem that waveform distortion occurs due to reflection and crosstalk.

An object of the present invention is to provide an optoelectronic integrated circuit capable of high-density mounting and capable of high-speed data transmission.

[0007]

The present invention has been made to achieve the above object, and in one aspect thereof, a semiconductor substrate and a general-purpose arithmetic processing which is formed on the semiconductor substrate and processes an electric signal. Section, a parallel / serial conversion section formed on the semiconductor substrate for converting a parallel electric signal output from the general-purpose arithmetic processing into a serial electric signal, and converting the serial electric signal into a parallel electric signal. A serial / parallel converter that outputs to the general-purpose arithmetic processing unit, an E / O converter that converts the serial electrical signal output from the parallel / serial converter to an optical signal and outputs the optical signal, and a serial electrical signal that receives the received optical signal. An O / E converter that converts the signal to output to the serial / parallel converter,
An optoelectronic integrated circuit comprising:

The above O / E converter and / or E
The / O converter may be arranged on the semiconductor substrate.

[0009] In another aspect, an optoelectronic integrated circuit having a light emitting / receiving section, an optical waveguide, and an input / output optical section for inputting / outputting light to / from the optical waveguide are provided, and the optical input / output section is the optoelectronic integrated circuit. There is provided an electronic device comprising: a mounting board provided with the optoelectronic integrated circuit, the mounting board being provided at a position facing the light emitting and receiving unit.

In this case, the light emitting / receiving section is provided on the bottom surface of the optoelectronic integrated circuit, and the light entering / exiting section is provided on the surface of the mounting substrate on which the optoelectronic integrated circuit is arranged. May be.

Further, the mounting substrate has a concave portion in which the optoelectronic integrated circuit can be arranged, the light input / output portion is provided on a wall surface of the concave portion, and the light emitting / receiving portion is the optoelectronic integrated circuit. May be provided on the side surface of the mounting board and arranged in the recess of the mounting board.

As another aspect, it has a substrate, an optical waveguide provided in an inner layer and / or a surface layer of the substrate, and an input / output unit capable of inputting / outputting light to / from the optical waveguide. A characteristic optoelectronic integrated circuit mounting substrate is provided.

In this case, the light entering / exiting portion may include a lens arranged on the surface layer of the substrate and a light reflecting member arranged below the lens.

Further, the substrate may have a concave portion in which the optoelectronic integrated circuit can be arranged, and the light entering / exiting portion may be arranged on an inner wall surface and / or a bottom surface of the concave portion.

The present invention will be described in more detail below.

An optical fiber or an optical waveguide is laid on the inner layer or surface of the printed board. On the other hand, an optical input / output mechanism having a light emitting / receiving element is provided on the bottom surface of the optoelectronic integrated circuit.

The light entering / exiting portion of the optical fiber or the optical waveguide is
It is preferable to use a fiber lens or the like to make the structure easy to optically couple.

[0018]

The electric signal output from the general-purpose arithmetic processing unit of the optoelectronic integrated circuit is converted into a serial electric signal by the parallel / serial conversion unit.

The electric signal is converted into an optical signal by the E / O converter and output.

The optical signal is input to the optical waveguide from the light entering / exiting portion of the optoelectronic integrated circuit mounting substrate, and is transmitted in the optical waveguide. Then, the optical signal is output from the light input / output unit provided corresponding to the optoelectronic integrated circuit on the receiving side.

The optoelectronic integrated circuit on the receiving side outputs the optical signal
The / E converter converts and outputs the serial electric signal. The serial / parallel conversion unit converts the serial electric signal into a parallel electric signal and inputs the parallel electric signal to the general-purpose arithmetic processing unit.

The data to be transmitted as described above has been conventionally transmitted in parallel with a large number of pins, but this is converted into parallel / serial data and a plurality of data pins are converted into one by utilizing the wide band property of light.
Since it can be replaced with a book fiber, the number of pins of the optoelectronic integrated circuit can be reduced.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

Before describing a specific mode, the concept of the present invention will be described with reference to FIG.

The present invention is characterized in that the optoelectronic integrated circuits are connected to each other by optical signals. In particular, the parallel / serial converter 72 and the E / O converter 74 are connected on the output side of each optoelectronic integrated circuit, and the serial / parallel converter 82 and the O / E converter 84 are connected on the input side. It is characterized in that it is built into one chip. In this figure, "CPU"
Reference numeral 70 denotes a general-purpose arithmetic circuit that is not dedicated to serial / parallel conversion processing or parallel / serial conversion processing. When the processing capacity of the "CPU" 70 is sufficiently high, the conversion is performed by the "CPU" 70, which is a versatile arithmetic circuit, without providing a dedicated serial / parallel conversion unit or parallel / serial conversion unit. Processing may be performed.

As described above, not only the "electrical pin" is simply replaced with the "optical pin" to speed up the data transmission, but also the serial / parallel conversion is internally executed to realize the optical conversion. The number of pins can be reduced by taking advantage of the large capacity and high speed of the fiber. As a result, mounting of the optoelectronic integrated circuit can be facilitated.

Specific embodiments will be described below.

FIG. 2 shows an optoelectronic integrated circuit which is an embodiment of the present invention.

In the optoelectronic integrated circuit 1a of this embodiment, the chip 102 is provided on one surface side of the optoelectronic integrated circuit substrate 100. Further, the light input / output mechanism 104a is provided on the surface facing the printed board in the mounted state. The chip 102 and the light input / output mechanism 104a are protected by the mold exterior 108. Note that the chip 102,
Power is supplied to the light input / output mechanism 104a by a power supply lead 106.

As described with reference to FIG. 1, the chip 102 is provided with the serial / parallel converter and the like.
The input / output of data to / from the optoelectronic integrated circuit 1a does not necessarily have to be performed entirely by an optical signal, and may be performed by an electrical signal through the lead 106 as necessary, as in the conventional case.

As shown in FIG. 3, the light input / output mechanism 104a is mainly composed of a light emitting element 12, a light receiving element 13, and a spherical lens 16.

The light emitting element 12 and the light receiving element 13 are optically coupled to a fiber lens 11 described later by a spherical lens 16. Further, the light emitting element 12 and the light receiving element 13 are
It is electrically coupled to a serial / parallel converter provided on the chip 102. As shown in FIG. 4, if the light emitting element 12 and the light receiving element 13 are separated and data is transmitted and received using separate fibers, light leaks from the light emitting element 12 to the light receiving element 13. It is possible to completely prevent malfunction.

The light emitting element 12 and the light receiving element 13 are also
It may be formed on the chip 102. In this case, it is preferable that the spherical lens 16 and the like are also arranged adjacent to the chip 102. However, it is not limited to this.

The printed board 5 on which the optoelectronic integrated circuit 1a of this embodiment is mounted will be described with reference to FIG.

The printed circuit board 5 is previously provided with an optical waveguide 6a such as an optical fiber. Then, the input and output of light to and from the optical waveguide 6a is performed from the light entering / exiting portion 8a. The light entrance / exit portion 8a is composed of a hole provided in the printed circuit board 5 and a fiber lens 11 arranged therein. The fiber lens 11 is used to improve the light coupling efficiency.

A reflection plate 7 for changing the direction of light is provided below the fiber lens 11. The reflection plate 7 is inclined at an angle of about 45 degrees, and the portion exposed to light has a high light reflectance by metal vapor deposition or the like.

The optical waveguide 6a preferably connects the optoelectronic integrated circuits as linearly as possible in order to reduce light transmission loss. Even when the optical waveguide 6a needs to be bent, it is preferable to make the angle as small as possible. Further, without using the fiber lens 11 and the reflection plate 7, as shown in FIG. 6, it is possible to bend the optical waveguide 6c laid on the printed circuit board 5 to directly form the light entering / exiting portion 8c. .. However, also in this case, it is necessary to make the bending radius of the optical fiber or the optical waveguide 6c sufficiently large in order to increase the light coupling efficiency.

A method of mounting the optoelectronic integrated circuit 1a will be described with reference to FIG.

By soldering the leads 106 of the optoelectronic integrated circuit 1a to the pads 3 of the printed circuit board 5, LS
The i1a is mounted on the printed circuit board 5. Needless to say, the position at which the optoelectronic integrated circuit 1a is fixed is a position at which optical signals can be reliably transmitted and received between the optical input / output mechanism 104a and the light input / output unit 8a. ..

The signal transmission will be described.

At the time of data transmission, the parallel signal output from the "CPU" in FIG. 1 is converted into a serial signal by the parallel / serial converter. Then, the serial signal is converted into light by the E / O converter, that is, the light emitting element 12 of the light input / output mechanism 104a. The optical signal 9 emitted from the light emitting element 12 passes through the fiber lens 11 and reaches the reflector 7. The optical signal 9 striking the reflecting plate 7 is reflected in a direction parallel to the printed board 5, and is transmitted to the light receiving element 13 of the optical input / output mechanism 4 provided in another optoelectronic integrated circuit 1a through the optical waveguide 6a. The light receiving element 13 converts the received optical signal into an electric signal and transmits the electric signal to the serial / parallel converter on the chip 102. Then, the converted parallel signal is input to the "CPU".

Another embodiment will be described.

As shown in FIG. 7, the optoelectronic integrated circuit 1b of this embodiment is basically the same as that shown in FIG. However, in this embodiment, the light input / output mechanism 10
The feature is that 4b is arranged on the side surface of the LS 11b.

A printed circuit board 5b for mounting the optoelectronic integrated circuit 1b will be described with reference to FIGS.

The printed circuit board 5b is provided with an element mounting hole 10 for mounting the optoelectronic integrated circuit 1b. An optical input / output unit 8b is provided on the wall surface at a position facing the optical input / output mechanism 104b in a state where the optoelectronic integrated circuit 1b is mounted. The details of the light input / output unit 8b are the same as those in the above-described embodiment except that the reflection plate 7 is not required.

If a certain standard is provided in the element mounting hole 10, the versatility of the printed circuit board 5b is increased, leading to cost reduction. Even in this case, as shown in FIG. 8, the optoelectronic integrated circuit 1b is mounted in the element mounting hole 10 by using the socket 110 having an adapter function between the element mounting hole 10 and each optoelectronic integrated circuit 1b. The optical input / output mechanism 104b and the optical input / output unit 8b are used.
Alignment with is easy.

A method of mounting the optoelectronic integrated circuit 1b on the printed board 5b will be described.

The optoelectronic integrated circuit 1b is fixed by soldering the leads 106 to the pads 3. In this case, the alignment of the optical waveguide 6b and the optical input / output mechanism 4 arranged on the side surface of the optoelectronic integrated circuit 1b is performed by the device mounting hole 1
Made easier by zero.

In this embodiment, since the light entrance / exit portion 8b is not arranged on the upper surface of the printed circuit board 5, it is hardly affected by dust and the like. It is also less susceptible to vibrations.

Another embodiment of the present invention will be described.

In the present embodiment, the transmission and reception of signals between adjacent optoelectronic integrated circuits is not performed through the optical waveguide provided on the printed circuit board, but is performed by directly transmitting the light in space.

As shown in FIG. 9, the optoelectronic integrated circuit 1c of the present embodiment is characterized in that the light input / output mechanism 104c is arranged on the side surface facing the adjacent optoelectronic integrated circuit 1c.

As shown in FIG. 10, the light input / output mechanism 104c has a transparent cover 15 for avoiding dust. Further, the lens used is not the spherical lens but the ordinary condenser lens 14. The other points are the same as those shown in FIG.

A J-bend type lead is used as the lead 106b for electrical connection with the printed circuit board 5. However, it is not limited to this.

The optoelectronic integrated circuit 1c is mounted on the lead 10
6b is soldered to the pad 3.

The printed circuit board 5c does not need to be provided with an optical waveguide or the like, and a conventional one can be used.

The transmission of optical signals will be described.

At the time of data transmission, the parallel signal output from the "CPU" in FIG. 1 is converted into a serial signal by the parallel / serial converter. Then, the serial signal is converted into light by the E / O converter, that is, the light emitting element 12 of the light input / output mechanism 104c.

The light emitted from the light emitting element 12 is converted into parallel light by the condenser lens 14a. The parallel light passes through the transparent cover 15 and the light receiving element 1 of the light input / output mechanism 4 arranged on the opposite side surfaces of the adjacent optoelectronic integrated circuit 1c.
Sent to 3. Further, the light emitted from the light emitting element 12 of the light input / output mechanism 4 on the other side is converted into parallel light by the transparent cover 1
5, the light is condensed by the condensing lens 14b, and is received by the light receiving element 13. The light receiving element 13 converts the received optical signal into an electric signal and transmits the electric signal to the serial / parallel converter on the chip 102. Then, the converted parallel signal is input to the "CPU". As a result, the data transmission between the adjacent optoelectronic integrated circuits 1c can be performed by the spatial light transmission. It is naturally possible to apply each of the above-mentioned embodiments to one optoelectronic integrated circuit.
The number of light input / output mechanisms 104 is also arbitrary.

Finally, the optical waveguide used in each of the above embodiments will be described.

The optical waveguide 6c is made of glass, a ferroelectric substance, a semiconductor, a magnetic substance, a polymer or the like. When the optical waveguide is arranged in the inner layer of the printed circuit board 5, if the height of the optical waveguide 6d is lower than the upper surface 52 of the inner layer substrate 50 as shown in FIG. Will be reduced. This can prevent distortion of the optical waveguide 6d and improve reliability.

As described above, in the above embodiment, the number of pins to be pulled out from the optoelectronic integrated circuit can be reduced, so that the optoelectronic integrated circuit can be easily mounted. Further, even when transmitting high-speed data, waveform distortion does not occur due to reflection or crosstalk.

[0063]

By transmitting data between optoelectronic integrated circuits by optical signals, it is possible to serially transmit data, which was transmitted in parallel with multiple pins, by optical signals. The number can be reduced, and high-density mounting is possible.
In addition, transmitting an optical signal has an effect of eliminating reflection and crosstalk that affect transmission data.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing the basic concept of the present invention.

FIG. 2 is a cross-sectional view showing the internal structure of an optoelectronic integrated circuit that is an embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a structural example of a light input / output mechanism 104 of the present embodiment.

FIG. 4 is a sectional view showing a structural example of a light input / output mechanism 104 of the present embodiment.

FIG. 5 is a cross-sectional view showing a state in which the optoelectronic integrated circuit of this embodiment is mounted on a printed board.

FIG. 6 is a vertical cross-sectional view showing another method of laying an optical fiber or an optical waveguide on a printed circuit board.

FIG. 7 is a cross-sectional view showing the internal structures of an optoelectronic integrated circuit and a printed circuit board according to another embodiment of the present invention.

FIG. 8 is a perspective view showing a state in which the optoelectronic integrated circuit of this embodiment is mounted using a socket.

FIG. 9 is a sectional view showing a state in which an optoelectronic integrated circuit according to another embodiment of the present invention is mounted on a printed board.

FIG. 10 is a cross-sectional view showing a structural example of a light input / output mechanism 104 of the present embodiment.

FIG. 11 is an explanatory diagram showing a relationship between an optical waveguide and an inner layer substrate.

FIG. 12 is a block diagram showing a concept of conventional LSI connection.

FIG. 13 is a perspective view showing a conventional LSI connection method.

[Explanation of symbols]

 1 ... Optoelectronic integrated circuit 3 ... Pad 5 ... Printed circuit board 6 ... Optical waveguide 7 ... Reflector 8 ... Light input / output section 9 ... Optical signal 10 ... Device mounting Hole 11 ... Fiber lens 12 ... Light emitting element 13 ... Light receiving element 14 ... Condensing lens 15 ... Transparent cover 16 ... Ball lens 50 ... Inner layer substrate 52 ... Top surface 70 ... CPU 72 ... Parallel / serial converter 74 ... E / O converter 82 ... Serial / parallel converter 84 ... O / E converter 100 ... Optoelectronic integrated circuit substrate 102 ... ..Chip 104 ... Optical input / output mechanism 106 ... Lead 108 ... Mold exterior 110 ... Socket

Claims (8)

[Claims] 1. A semiconductor substrate, a general-purpose arithmetic processing unit formed on the semiconductor substrate and processing an electric signal, and a serial electric parallel signal output from the general-purpose arithmetic process formed on the semiconductor substrate. Parallel / serial conversion unit for converting into a parallel electric signal and a serial / parallel conversion unit for converting a serial electric signal into a parallel electric signal and outputting the parallel electric signal to the general-purpose arithmetic processing unit, and a serial / parallel conversion unit output from the parallel / serial conversion unit. An E / O conversion unit that converts an electric signal into an optical signal and outputs the optical signal, and an O / E conversion unit that converts the received optical signal into a serial electric signal and outputs the serial electric signal to the serial / parallel conversion unit are provided. A characteristic optoelectronic integrated circuit. 2. The optoelectronic integrated circuit according to claim 1, wherein the O / E converter and / or the E / O converter is disposed on the semiconductor substrate. 3. An optoelectronic integrated circuit having a light emitting / receiving part, an optical waveguide, and a light input / output part for inputting / outputting light to / from the optical waveguide, wherein the light input / output part is the light receiving / emitting part of the optoelectronic integrated circuit. An electronic device, comprising: a mounting substrate on which the optoelectronic integrated circuit is disposed, the mounting substrate being provided at a position facing the electronic device. 4. The light emitting / receiving unit is provided on the bottom surface of the optoelectronic integrated circuit, and the light input / output unit is provided on the surface of the mounting substrate on which the optoelectronic integrated circuit is arranged. Claim 3
Electronic device as described. 5. The mounting substrate has a concave portion in which the optoelectronic integrated circuit can be arranged, the light incident / exiting portion is provided on a wall surface of the concave portion, and the light emitting / receiving portion is the optoelectronic integrated circuit. The electronic device according to claim 3, wherein the electronic device is provided on a side surface of the electronic component and is disposed in the concave portion of the mounting substrate. 6. An optoelectronic device comprising: a substrate; an optical waveguide provided on an inner layer and / or a surface layer of the substrate; and an input / output unit capable of inputting / outputting light to / from the optical waveguide. Substrate for mounting integrated circuits. 7. The light entering / exiting portion includes a lens arranged on the surface layer of the substrate and a light reflecting member arranged below the lens. Substrate for mounting optoelectronic integrated circuits. 8. The substrate according to claim 6, wherein the substrate has a concave portion in which an optoelectronic integrated circuit can be arranged, and the light entering / exiting portion is arranged on an inner wall surface and / or a bottom surface of the concave portion. Substrate for mounting optoelectronic integrated circuits.