JPH01109758A - Large scale logic integrated circuit - Google Patents

Abstract

PURPOSE:To improve an integration density, by inputting input signals at a plurality of different frequencies, and selectively detecting the signals. CONSTITUTION:Light beams are projected on a large scale logic integrated circuit on a substrate 1 from a light emitting element 2 with a wavelength fA and a light emitting element 3 with a wavelength fB. Meanwhile, optical detectors 4 and 5 are arranged at places, where synchronizing signals are required in the logic integrated circuit. The detecting wavelengths of the optical detectors 4 and 5 are changed in correspondence with the kinds of the synchronizing signals. As a result, for the light signal having the wavelength fA, several detectors 4 are operated. For the light signal having the wavelength fB, the group of the other detectors 5 are operated. In this way, the wavelengths for the light signals are prepared in correspondence with the number of the input signals. The detectors 4 and 5 are also prepared in correspondence with the number of the input signals. Thus the arbitrary synchronizing signal can be transmitted to an arbitrary place in the integrated circuit. Since a plurality of the synchronizing signals can be inputted to any places on the LSI without delay, the level of integration is improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to large-scale logic integrated circuits, and particularly to extremely large-scale logic integrated circuits that have a very large number of gates and the delay time of synchronization signals cannot be ignored using conventional electrical wiring. The present invention relates to a synchronization signal input device for a logic integrated circuit.

[Conventional technology]

In conventional large-scale logic integrated circuits, in order to operate each logic circuit in synchronization, synchronization signals were often electrically input from the outside. However, the scale of the logic circuit has increased, requiring a plurality of synchronization signals, and the delay time of the synchronization signal on the integrated circuit cannot be ignored, so it is necessary to adjust this delay time.

This hindered the improvement of the degree of integration. On the other hand, there is a method of inputting a synchronized signal to all locations within the chip by inputting the synchronization signal using light.
E E E E Magazine (Proceedings of
IEEE Volume 72, No. 7, pp. 850-866 (1
984). However, the purpose of this paper is to operate all the circuits in the chip with the same synchronization signal, and it is not possible to handle multiple synchronization signals.

[Problem that the invention seeks to solve]

In the above conventional technology, the signal input to the integrated circuit is inputted via the wiring on the integrated circuit, so the signal delay in the wiring cannot be ignored.Also, there is no problem of delay when inputting with light, but when multiple input signals are input, The problem was that it couldn't be handled.

An object of the present invention is to eliminate the above-mentioned problems and to input a plurality of synchronization signals throughout the chip.

[Means for solving problems]

The above object is achieved by inputting an input signal at a plurality of different wavelengths and selectively detecting the signals.

FIG. 1 shows a basic conceptual diagram of the present invention. In a large-scale logic integrated circuit formed on a semiconductor substrate 1, the part indicated by A is driven by a synchronizing signal S^, and the part indicated by B is It is driven by a synchronization signal Sa. Here, the large-scale logic integrated circuit is irradiated with light by the light emitting element 2 having the wavelength f^ and the light emitting element 3 having the wavelength fa.

[Effect]

On the other hand, optical detectors 4 and 5 are arranged at locations in the logic integrated circuit where a synchronization signal is required, and the detection wavelength of these optical detectors is changed depending on the type of synchronization signal. As a result, the wavelength f^
Several detectors 4 operate for optical signals of wavelength fB
Another group of detectors 5 is operated for the optical signals. In this way, by preparing the wavelength of the optical signal according to the number of input signals and preparing the detector accordingly, it becomes possible to transmit an arbitrary synchronization signal to an arbitrary case within the integrated circuit.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. 2
In a large-scale logic integrated circuit that requires a synchronizing signal input, the input signal wavelength of one circuit All is set to 1.2 μm and the input signal wavelength of circuit B12 is set to 0.8 μm, respectively.
For a wavelength of 1.2 μm as a signal detector, I n
o, sG a o, IIA For a wavelength of 0.8 μm, the heterojunction of s7 and InP6 is G ao + 6I n
o, 5P 8 and G ao, III no@l5Aso,
The iPo and δ9 heterojunctions were each stacked on the Si substrate 13 and used. As a result, it has become possible to input synchronization signals with no phase difference at all to each circuit 11 and 12 of the large-scale logic integrated circuit, and it has also become possible to input two types of synchronization signals completely independently. In this example, examples of InGaAs and InP and GaInP and GaInAsP are shown, but it goes without saying that other compound elements and wavelengths may be combined.

Another embodiment of the present invention will be described. In large-scale logic integrated circuits that require three types of synchronization signal input, three types of input signal light, red light, green light, and blue light, are used, and a normal MO8 element is used as a signal detector to detect A filter combining an infrared ray removal filter and filters 16, 17, and 18 that pass only red, green, and blue light was placed in the light incident part of the device. As a result, it is possible to input three types of synchronizing signals, and a separation ratio of 30 dB or more can be obtained.
It was possible to input each signal completely independently.

In this example, an MO8 element was used as a detector, but a CCD
elements, bipolar transistors, photodiodes, etc.
It goes without saying that other photodetectors may be used.

〔Effect of the invention〕

According to the present invention, a plurality of synchronization signals can be inputted to any location on the LSI without delay, so that it is possible to improve the operating speed, size, and performance of a large-scale logic LSI.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an integrated circuit illustrating the concept of the present invention. FIG. 2 is a perspective view and a vertical sectional view of an integrated circuit showing one embodiment using a Peter junction element as a photodetector, and FIG. 3 is a perspective view and a longitudinal sectional view showing another embodiment of the present invention. . 1... Substrate, 2... Light emitting element (wavelength A), 3...
Light emitting element (wavelength B), 4... Light receiving element (sensing wavelength A), 5... Light receiving element (sensing wavelength B), 6... In
P, 7-InGaAs, 8-GaInP, 9...G
aInAsP, 10... Diffusion layer, 11... A circuit region, 12... B circuit region, 13... Si substrate, 1
4... Light receiving element (sensing wavelength C), 15... C circuit area, 16... Filter 1 (passes only red light),
17... Filter 2 (passes only green light), 18...
... Filter 3 (passes only blue light), 19 ... Insulating film layer, 20 ... VA to source drain diffusion d

Claims (1)

[Claims] 1. In a large-scale logic integrated circuit in which it is necessary to input at least two or more types of synchronization signals in order to perform circuit operation, the input signals are inputted with two or more types of light having different wavelengths,
A large-scale logic integrated circuit characterized in that the integrated circuit is provided with a detector having the ability to selectively detect each optical wavelength.