JP2942811B2 - Superconducting logic integrated circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a superconducting logic integrated circuit mounted on a substrate chip, and more particularly to an improvement in supplying high-frequency power.

[0002]

2. Description of the Related Art When a superconducting logic integrated circuit generally called a Josephson logic integrated circuit or the like is mounted on a substrate chip and operated, the superconducting integrated circuit usually has a considerably low impedance. An impedance conversion circuit is required between the high-frequency power source, which is an operating power source and is external to the substrate chip, and the superconducting logic integrated circuit in order to match the power supply impedance on the substrate chip. .

FIGS. 2A and 2B schematically show an example of a conventional planar configuration in such a case, which is mounted on a substrate chip 10 having a large number of bonding pads 11 around it. , to the power supply superconducting integrated circuit 13 running supplied with source power, external high-frequency power source
An impedance conversion circuit 12 is provided on the same substrate chip 10 in order to supply high frequency power from φ .

In the case of FIG. 2A, the impedance conversion circuit 12 includes a plurality of bonding pad groups 11,.
, A primary side is connected to a pair of bonding pads 11, 11 to which an external high-frequency power source φ is connected, and a middle point of the secondary side is connected.
Superconducting transformer T having a DC bias voltage dc applied thereto.
R and voltage regulators RG, R provided one by one for each polarity output of the secondary side of the superconducting transformer TR, each being constituted by a series circuit of a plurality of Josephson junctions.
G for so-called two-phase pulsating power supply .

On the other hand, in the case of FIG. 2B, the impedance conversion circuit 12 is composed of an inductor L in series with one of the pair of power supply lines and a pair of capacitors C and C extending between the pair of power supply lines. And a voltage regulator RG provided between a pair of power supply lines. Since this is in principle for supplying a single-phase pulsating current, in order to supply two-phase pulsating current in general, two not shown are used, each of which is used as an external high-frequency power source. Connect to high frequency outputs with different phases.

[0006]

[Problems to be Solved by the Invention] However, FIG.
In the superconducting logic integrated circuit of this type, the power supply waveform itself is a clock in the semiconductor integrated circuit, regardless of the specific configuration of the impedance conversion circuit 12 related to the high-frequency power supply, including the configuration shown in FIG. In addition, since high-speed operation of 1 GHz or more is generally desired, a layout pattern such as that shown in FIGS. 2A and 2B requires an impedance conversion circuit (power supply). The phase shift (skew) of the power supply waveform in the power-supplying superconducting integrated circuit 13 becomes a problem depending on the geometric distance from the circuit 12 or the length of the power supply line wiring.
Naturally, the degree of the phase shift increases as the size of the integrated circuit chip increases. Nevertheless, conventionally, there is no doubt about the arrangement itself as shown in FIGS. 2A and 2B, and conversely, the time corresponding to the phase shift is an idle time not used for the logical operation. In a sense, only passive measures have been taken, which has been a major constraint on further increasing the speed of circuit operation.

[0007]

SUMMARY OF THE INVENTION In order to solve the problems in the prior art, the present invention divides a power-supplied superconducting integrated circuit into a plurality of rectangular portions, and separates each of the divided logical integrated circuits. For each of the circuit parts,
An impedance conversion circuit is provided for converting the power supply power from the external high-frequency power supply into impedance.

Further, in the present invention, after satisfying the above basic configuration, the plurality of divided logic integrated circuit parts are divided into two sets belonging to a first set and a second set, and the logic integrated circuit parts belonging to the first set are divided. And a group of impedance conversion circuits provided for each of the logic integrated circuits belonging to the second set, the phases of the impedance conversion circuits provided from the external high-frequency power source. A configuration that provides 180 ° different high-frequency power supply is also proposed. In this way, in this type of superconducting logic integrated circuit, fluctuations in the ground potential provided on the substrate chip, that is, fluctuations in the reference potential (ground potential) are generally suppressed.

[0009]

FIG. 1 shows a superconducting logic integrated circuit which is an improvement of the conventional example shown in FIG. 2A as an embodiment constructed in accordance with the present invention. Therefore, corresponding components are denoted by the same reference numerals as in FIG. 2, but in the present invention, first, in the conventional configuration as shown in FIG. The supply superconducting integrated circuit 13 is divided into a plurality of circuit parts 13-1 to 13-4 on the same substrate chip 10. In the case shown in the figure, the number of divisions is "4" as a result of dividing into two parts left and right and two parts up and down, and each of the divided circuit parts 13-1 to 13-4 has a square shape of the same size (same area). I am trying to be.

Then, the divided first to fourth circuit portions 13
-1 to 13-4 have dedicated impedance conversion circuits
12-1 to 12-4 are provided. In the case shown in the figure, each of the impedance conversion circuits 12-1 to 12-4 is for two-phase pulsating power supply using the superconducting transformer TR as already described with reference to FIG. High-frequency power is applied from the high-frequency power source via the corresponding bonding pads 11, 11, respectively.

Particularly in this regard, in the illustrated embodiment, the first to fourth circuit portions 13-1 to 13-
4 is further divided into two sets, and the first and third circuit portions 13- belonging to the first set, which is the left half on the substrate chip 10 in the drawing.
Impedance conversion circuits 12-1 and 1 for 1, 13-3
A high-frequency power supply is supplied to the power supply circuit 2-3 at the same phase from the first-phase high-frequency power supply φ-1, and the remaining second and fourth circuit portions 13-2 and 13-4 belonging to the second group are provided. The second phase high frequency power has the same phase with respect to the impedance conversion circuits 12-2 and 12-4 attached thereto but has a 180 ° phase difference from the first phase high frequency power source φ-1. The high frequency power is supplied from the source φ-2. What
Each of the impedance conversion circuits 12-1 and 12-3
A desired pulsating power supply wave is located at the secondary midpoint of the superconducting transformer TR.
DC bias voltage dc according to known techniques to obtain shape
-1 is given, and the impedance conversion circuit 12-
At the secondary midpoint of each superconducting transformer TR in 2,12-4
Is supplied with a DC bias voltage dc-2. Only
These are DC vias that are applied statically.
Voltage, the length of the routing wiring has little effect.
No, and even if the phase differs between the first and second phases,
In order to obtain a similar power supply power waveform,
Bias voltages dc-1 and dc-2 are equal in magnitude to each other
Is good.

The superconducting logic integrated circuit of this embodiment is constructed as described above.
Assuming that -1 to 13-4 form a square, each of the circuit portions 13-1 to 13-4 has a quarter in area as compared with the conventional example shown in FIG. , The maximum wiring length for each circuit portion is also halved, and the skew that can occur in each circuit portion is also halved. The idle time (the time that cannot be used for the logical operation) is reduced to less than half in principle. In other words, according to the present invention, the operation time of the superconducting logic integrated circuit as a whole can be shortened only by devising a simple arrangement.

Of course, each of the divided circuit parts 13-1 to 13
-4 is desirably a square in a planar geometric shape, but may be a rectangle. Also in this case, the effect of improving the operation speed according to the present invention can be obtained according to the ratio of the long side of the rectangle to the long side of the conventional circuit shown in FIG. 2 (or one side in the case of a square). .

Further, in the above-described embodiment, the divided circuit portions 13-1 to 13-4 are divided into first and second sets, and the first and second high-frequency power sources φ- with different phases by 180 °, respectively. Since it is driven by 1, φ-2, this is a so-called balanced power supply system, and it is desirable to be able to reduce the potential fluctuation of the ground used in this type of superconducting logic integrated circuit.

In the case shown in the drawing, both the first-phase high-frequency power source φ-1 and the second-phase high-frequency power source φ-2 are shown in the upper part of the drawing, respectively, for convenience of illustration in a limited space. Although only shown, if such is done in an actual arrangement, a phase shift may occur in the same set. That is, regarding the first part 13-1 and the third part 13-3 driven by the first-phase high-frequency power source φ-1, the respective impedance conversion circuits 12-1, If there is a difference in the length of the line wiring up to 12-3, a skew corresponding to the difference occurs. If the difference in the wiring distance exceeds a certain level, the skew may not be negligible. The same applies to the second set. Therefore, if this is not desirable, the first-phase and second-phase high-frequency power sources φ-1, φ-2
From the corresponding impedance conversion circuits 12-1,
12-3: The geometrical installation positions of the high-frequency power sources φ-1 and φ-2 may be determined at positions where the wiring lengths to 12-2 and 12-4 are the same.

Of course, the illustrated embodiment can be applied to the case where a different type of impedance conversion circuit such as the filter type shown in FIG. 2B is used, and the number of divisions of the superconducting logic integrated circuit as a whole. Can be expanded to any number. The same applies to the grouping, and basically, it is sufficient to include the configuration divided into the groups belonging to the first and second sets which are different from each other by 180 ° with respect to the phase of the supplied high frequency power.

[0017]

According to the present invention, the maximum wiring length related to the power supply can be greatly reduced as compared with the conventional case, so that the skew can be reduced and the idle time can be shortened, so that the logic operation can be performed at a higher speed than before. become.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a superconducting logic integrated circuit configured according to the present invention.

FIG. 2 is a schematic configuration diagram of a conventional superconducting logic integrated circuit.

[Explanation of symbols]

10 Substrate chip, 11 Bonding pad, 12-1, 12-2, 12-3, 12-4 Impedance conversion circuit, 13-1, 13-2, 13-3, 13-4 Superconducting logic integrated circuits Part, φ-1 first phase high frequency power source, φ-2 second phase high frequency power source.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Susumu Takada 1-1-4 Umezono, Tsukuba, Ibaraki Pref., National Institute of Advanced Industrial Science and Technology (56) References Japanese Patent Laid-Open No. 2-184088 (JP, A) Nao Hayakawa "4. Ultra-high-speed Josephson Device", Baifukan (First Edition, November 30, 1986), pp. 264-276 (58) Fields investigated (Int. Cl. ⁶ , DB name) H01L 39/22 H01L 39 / 24 H01L 39/00 H01L 39/02 H01L 21/82 H03K 19/195

Claims (3)

(57) [Claims] 1. A superconducting logic integrated circuit mounted on a substrate chip and operated by receiving high-frequency power supply power is divided into a plurality of square logic integrated circuit portions on the substrate chip; A superconducting logic integrated circuit, wherein an impedance conversion circuit is provided on the chip for impedance matching between the plurality of divided logic integrated circuit portions and an external high-frequency power source; 2. The superconducting logic integrated circuit according to claim 1, wherein said plurality of divided logic integrated circuit parts are divided into a part belonging to a first set and a part belonging to a second set; The group of the impedance conversion circuits provided for each of the plurality of logic integrated circuits belonging to the set, and the impedance conversion circuit provided for each of the plurality of logic integrated circuits belonging to the second set. Providing a group with high-frequency power having a phase difference of 180 ° from the external high-frequency power source; 3. The superconducting logic integrated circuit according to claim 2, wherein each of said impedance conversion circuits provided for each of said plurality of logic integrated circuits belonging to said first set and said first logic circuit. The wiring distances between the high-frequency power sources for the set are all equal, and each of the impedance conversion circuits provided for each of the plurality of logic integrated circuits belonging to the second set and the second set A superconducting logic integrated circuit, wherein the wiring distances to the high-frequency power source are all equal.