JPH04239759A - Electronic device - Google Patents

Abstract

PURPOSE:To eliminate a propagating delay time difference by providing an optical signal processor having a photodetector at each of a plurality of unit circuit blocks to receive an input signal as an optical signal and converting it to an electric signal. CONSTITUTION:When optical input signals 80 in which strong and weak are repeated in an operation clock frequency, are simultaneously emitted on a semiconductor substrate 60, photodetector blocks 15 of unit logical circuit blocks 31, 33 are operated as clock signal generators which output H, L levels in the clock frequency of the signals 80. In this case, since the light simultaneously arrives at photodiodes 16 as its properties, a propagating delay time difference of the clock signals does not occur between the blocks 15. Since the signals 80 are emitted to the entire substrate 60, the signals are not necessarily sent via wirings fixed on the substrate, and the blocks 31, 33 can be disposed at arbitrary positions on the board 60 without considering the lengths of wirings.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electronic devices, and more particularly to an improvement in a method for supplying input signals to a plurality of unit circuit blocks constituting an electronic device.

0002

[Prior Art] An example of the prior art related to this invention is shown in FIG.
Explain using. Generally, one electronic device can be divided into a plurality of blocks, and FIG. 3 shows the configuration of a conventional electronic device in which the circuit configuration is divided in this way. In the figure, 10 is a clock signal input terminal for inputting a clock signal. 21 to 27 are first to second parts constituting the electronic device;
This is the seventh unit circuit block. Reference numerals 101 to 107 indicate first to seventh clock signal wirings that supply clock signals from the input terminal 10 to each unit circuit block 21 to 27. Here, these clock signal wirings 101 to 107
As shown in the figure, one exists for each unit circuit block. 41 to 43 are output terminals other than the clock input terminals of the first, third, and seventh unit circuit blocks 21, 23, and 27.

In such an electronic device, the clock signal supplied to the input terminal 10 is transmitted through each of the clock signal wirings 1 described above.
It is supplied to each unit circuit block 21-27 via 01-107. Each block 21 to 27 performs a predetermined operation based on the clock signal.

0004

However, in general, it is difficult to connect the clock signal input terminal 10 to each unit circuit block 21 to 2.
The clock signal wirings 101 to 107 up to 7 have different wiring lengths. Therefore, due to the difference in wiring length, a difference occurs in the propagation delay time of the clock signal in each of the clock signal wirings 101 to 107, and the operation timings of the unit circuit blocks 21 to 27 do not match.

[0005]Although it is possible to make the lengths of each clock signal wiring approximately equal to reduce the difference in propagation delay time between each clock signal wiring, it is not possible to make them completely equal. Furthermore, if the circuit configurations, etc. of each unit circuit block are not the same, the area of each unit circuit block will be different. Therefore, each unit circuit block should be arranged so that the lengths of the clock signal wirings corresponding to these blocks are equal. becomes difficult. Furthermore, problems such as waveform distortion and propagation delay time differences due to wiring resistance and capacitance components, and interference between adjacent wirings are unavoidable.

Furthermore, in an electronic device, when light is incident on the electronic circuit constituting the device, the signal value of the electronic circuit may change. This is because light affects the energy of electrons and anodes that are the signal medium of electronic circuits, but changes in the signal values of electronic circuits can also lead to malfunctions of electronic devices.

The present invention was made to solve the above-mentioned problems, and it is possible to prevent the occurrence of a difference in signal propagation delay time to each unit circuit block without causing restrictions on the layout of each unit circuit block. It is an object of the present invention to provide an electronic device that can reduce the amount of noise.

Another object of the present invention is to provide an electronic device that not only prevents the occurrence of signal propagation delay time differences but also has fewer malfunctions due to the incidence of light.

[0009]

[Means for Solving the Problems] An electronic device according to the present invention includes a plurality of unit circuit blocks formed on a substrate.
It is equipped with an optical signal processing section that has a light receiving element and receives an input signal as an optical signal and converts it into an electrical signal.

[0010] Furthermore, the present invention provides the above electronic device, which includes:
A portion of the substrate other than the area where the light-receiving element is arranged is shielded from light by a light-shielding material.

[0011]

[Operation] In this invention, since an optical signal processing section that receives an input signal as an optical signal and converts it into an electrical signal is arranged in each of a plurality of unit circuit blocks, the input signal is directly supplied to each unit circuit block. This eliminates the need to propagate the input signal from the input terminal to each unit circuit block via wiring. Therefore, it is possible to eliminate the effects of differences in wiring length, interference between wirings, and variations in resistance and capacitance components of each wiring, and also to eliminate differences in propagation delay times caused by these. At the same time, since there is no need for electrical signal propagation wiring, each unit circuit block can be freely arranged without considering differences in wiring path lengths from predetermined input terminals and the like.

[0012] Furthermore, since the portion of the substrate other than the area where the light receiving element is arranged is shielded from light, it is possible to prevent light from entering the circuit portion other than the light receiving element, thereby suppressing malfunction of the circuit due to light irradiation. I can do it.

[0013]

[Embodiment] FIG. 1 is a diagram for explaining an electronic device according to an embodiment of the present invention. In the figure, 61 is a semiconductor circuit provided on a semiconductor substrate 60, and the first to eighth units are It has logic circuit blocks (unit circuit blocks) 31 to 38. Each unit logic circuit block includes a light receiving element block (optical signal processing section) 15, logic circuits such as an AND gate and an OR gate, which operate using the output of the light receiving element block 15 as a clock signal, a counter, a memory, and the like. are doing. Reference numeral 80 denotes a parallel optical input signal that is irradiated onto the entire surface of the semiconductor substrate 60 and repeats its strength and weakness based on the operating clock frequency of the logic circuit. Here, the light-receiving element block 15 includes a photodiode (light-receiving element) 16 that converts the optical input signal 80 into an electrical signal, and an amplifier 17 that outputs 'H' level and 'L' level depending on the strength of the light. It is configured. Also 51~
53 is wiring between predetermined unit logic circuit blocks, 41 to 4;
5 is an output terminal of the unit logic circuit block.

Note that the detailed configuration of the light receiving element block 15 is shown only for the first unit logic circuit block 31 in the figure.
That is, the photodiode 16 and the amplifier 17 are shown, and for the other unit logic circuit blocks 32 to 38, the light receiving element blocks are shown by circular hatched areas 15.

Next, the functions and effects will be explained. When the optical input signal 80 which repeats the strength and weakness at the above operating clock frequency is irradiated onto the semiconductor substrate 61 all at once, the light receiving element blocks 15 of each unit logic circuit block 31 to 38 are at the 'H' level at the operating clock frequency of the optical input signal 80. , 'L
'It works as a clock signal generator that outputs the level. At this time, since the light reaches each photodiode 16 at the same time by its nature, no difference in propagation delay time of the clock signal occurs between the respective light receiving element blocks 15. In addition, since the optical input signal 80 is irradiated to the entire semiconductor substrate 60, there is no need to send the signal through fixed wiring on the semiconductor substrate, and each unit logic circuit block 31 to 38 can be connected without considering the wiring length. can be freely placed at any position on the semiconductor substrate 60. In addition, since there is no need to provide clock signal wiring for each unit logic circuit block, there is no need to provide clock signal wiring for each unit logic circuit block.
There is no influence of variations in capacitance components. In other words, it is possible to significantly reduce signal deterioration and differences in propagation delay time differences due to differences in the length of capacitance and resistance components of wiring.

Next, a second embodiment of the present invention will be described. FIG. 2 is a schematic diagram showing the configuration of an electronic device according to a second embodiment of the present invention.
a second unit logic circuit block, 60 a semiconductor substrate, 15
receives the optical input signal 80 and outputs 'H' depending on the strength of the light.
This is a light receiving element block that outputs 'level' and 'L' level, and consists of a photodiode 16 and an amplifier 17. These are the same as the device of the first embodiment described in FIG.

Reference numeral 70 denotes a light-shielding material having openings 71 only in the portions of the semiconductor substrate 60 corresponding to the photodiode 16 arrangement portions of the respective unit circuit blocks 31 and 32, covering the entire surface of the semiconductor substrate 60. There is. For easier understanding, Figure 2(b) shows IIb-I in Figure 2(a).
A cross-sectional structure taken along line Ib is shown.

Generally, when light enters a semiconductor circuit, it excites the electrons and atoms of the anode, which are the signals of the semiconductor circuit, and may cause malfunction, but in addition to the effects of the above-mentioned embodiment, the device of this embodiment has the following effects: Since the semiconductor substrate 60 is covered with a light shielding film having an opening 71 in a portion corresponding to the photodiode 16 arrangement portion, the optical input signal 80 is incident only on the photodiode 16 portion, and light is not transmitted to other circuit portions. The light incident thereon is blocked, which also has the effect of preventing malfunctions of the semiconductor circuit 61 caused by light.

In each of the above embodiments, a photodiode is shown as a light receiving element that converts an optical signal into an electrical signal, but a photo-electrical conversion element such as a phototransistor may also be used.

Furthermore, in the above embodiments, each unit logic circuit block has been described as an example of a semiconductor circuit in which one light-receiving element is on-chip. It may be constructed of an electronic component and one or more photoelectric conversion elements, and an optical input signal may be input to each photoelectric conversion element using, for example, an optical fiber having the same length.

Further, in the above embodiment, an example is shown in which an optical input signal having two levels, strong and weak, is used as a digital clock signal input, but the input signal may be a digital data input signal other than a clock input, or the input signal may be a digital data input signal other than a clock input. The signal may not be a digital signal but may be an analog signal that changes the intensity of light, and may be supplied at the same timing to a plurality of unit circuit blocks each having an analog signal processing circuit or an analog-to-digital conversion circuit.

Furthermore, each light receiving element is provided with a filter that transmits only a specific wavelength, or a photoelectric conversion element that operates only for signals of a specific wavelength is used as the light receiving element,
By changing the data, that is, the timing of strength and weakness, etc., depending on the wavelength, the light receiving elements of each unit circuit block can be operated at different timings, and different data, that is, different unit logic circuit blocks require each. It is possible to send data to each unit logic circuit block simultaneously.

[0023]

As described above, according to the electronic device according to the present invention, each of a plurality of unit circuit blocks has an optical signal processing section that has a light receiving element and receives an input signal as an optical signal and converts it into an electrical signal. Since the input signal is placed directly into each unit circuit block, there is no need to propagate the input signal from the input terminal to each unit circuit block via wiring, and this eliminates the need for differences in wiring length and interference between wiring. and the resistance of each wiring,
This has the effect of eliminating propagation delay time differences caused by variations in capacitance components. Furthermore, since wiring for propagating electrical signals is not required, each unit circuit block can be freely arranged without considering differences in wiring path lengths from predetermined input terminals and the like.

Further, according to the present invention, in the above-mentioned electronic device, a portion of the substrate other than the portion where the light-receiving element is arranged is shielded from light. This has the effect of suppressing circuit malfunctions caused by light irradiation.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of an electronic device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of an electronic device according to a second embodiment of the present invention.

FIG. 3 is a diagram showing a configuration example of a conventional electronic device.

[Explanation of symbols]

15 Light receiving element block (optical signal processing section) 16 Photodiode (light receiving element) 31 to 38
1st to 8th unit logic circuit blocks

Claims (2)

[Claims] 1. An electronic device having a plurality of unit circuit blocks formed on a substrate and operating based on a predetermined input signal, each of the unit circuit blocks having a light receiving element and converting the input signal into an optical signal. What is claimed is: 1. An electronic device comprising: an optical signal processing section that receives signals as signals and converts them into electrical signals. 2. The electronic device according to claim 1, wherein a region on the substrate other than the area where the light receiving element is arranged is shielded from light by a light shielding material.