JPS6257246A - Integrated circuit of field effect type semiconductor element - Google Patents

Abstract

PURPOSE:To make the interval from the time when each output signal line is connected to a power source having the first potential to the time when the first potential is reached not very long, even if the number of field-effect type semiconductor elements in cascade connection between the output signal lines and the power source having the first potential is increased,by combining a plurality of the field-effect type semiconconductor elements into one field-effect type semiconductor elements into one field-effect type semiconductor element. CONSTITUTION:The gates of elements S211-S214 are connected to the same input signal line, and the second electrodes are connected to the same potential point. Therefore the elements can be combined into one element 16e. Similarly, elements S201-S204 can be combined into one element 16f. The gate pairs of elements S113 and S114, S103 and S104, S111 and S112, and S101 and S102 are connected to the same input signal line, and the second electrodes are connected to the same potential point. Therefore, they can be combined into elements 16c, 16d, 16b and 16a. The gate widths of the combined elements are expanded in correspondence with the number of the original elements, and an ON resistance is lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a field effect semiconductor element integrated circuit, and particularly to a case where a ROM is constructed by cascade connection.

[Conventional technology]

FIG. 3 is an explanatory diagram showing an example of a conventional field-effect semiconductor element integrated circuit of this type, and FIG. 4 is an equivalent circuit diagram of the integrated circuit shown in FIG.

121, +3), [41, +51, [6)
are input signal lines arranged in parallel, +71, +81,
+91, (10), (11), (12), (13
), (14) are each input signal line 111, +21
, +31 , 141 , +51 , +6), and output signal lines (15) are arranged in parallel in a direction perpendicular to the direction of the output signal lines 1'! position part, (16
) is a field effect semiconductor device.

Input signal line (1), cutting 1.131, [4), 15)
, (6) and the output signal line (7).

(81, +'J, (10), (11), (12),
Field-effect semiconductor elements (1
6), and the gates of each field effect semiconductor element (16) are connected to input signal lines 111, +21, +3, respectively.
1 of +, +41, +51, +61
Connect to each output signal line +71, +81, +
91, (10), (11), (12).

The field effect semiconductor elements (16) on each extension line of (13) and (14) are cascade-connected, and the field effect semiconductor elements (16) on each extension line are connected in cascade with these output signal lines. It is configured to be connected to the first potential section (15) via the first potential section (15).

Multiple input signal lines fil, +21, (31,
For example, when three input signal lines fil, +31, and +51 among +41, +51, and +61 reach a potential that turns on the field-effect semiconductor element (16), the gate turns on the three input signal lines (16). ).

12 field effect semiconductor elements (16) connected to +31 and +51 (5OOI, 800 in Figure 4)
2 Among the elements numbered 5011 to 8014
, 5ill~2114.

When the 12 elements (5211 to 5214) are turned on, the output signal line (14) is electrically connected to the 1%L portion (15) via the elements 5O14, 5114, and 5214.

In this way, a state in which only a certain output signal line is connected to a power supply having a first potential according to the logic determined by the layout of the field effect semiconductor element is created by combining the respective potentials of the plurality of input signal lines. is obtained and a ROM is constructed.

[Problem that the invention seeks to solve]

Since the conventional ROM field-effect semiconductor element integrated circuit is configured as described above, a large number of field-effect semiconductor elements are connected in cascade between the output signal line and the power supply having the first potential. Then, the on-resistances of the field-effect semiconductor elements are added up, and from the time when the output signal line and the power supply having the first potential are electrically connected until the output signal line reaches the first potential, the on-resistance of the field-effect semiconductor element is added up. The problem was that it took a lot of time.

In order to shorten this time, the method of increasing the gate width of each field effect semiconductor element to lower the on-resistance has the disadvantage that the pattern area becomes large.

This invention was made in view of the above circumstances, and even if the number of cascade-connected field effect semiconductor elements increases,
A field-effect semiconductor element integrated circuit whose pattern area is the same as that of conventional circuits and whose output signal line does not take too long from being connected to a power source having a first potential to reaching the first potential. The purpose is to provide.

[Means for solving problems]

The field-effect semiconductor element integrated circuit according to the present invention combines a plurality of field-effect semiconductor elements whose gates are connected to the same input signal line and whose second electrodes are connected to the same potential point into one field-effect semiconductor element. It is a type of semiconductor device.

[Effect]

By combining a plurality of field effect semiconductor elements into one field effect semiconductor element, the gate width can be increased and the on-resistance can be lowered.

[Embodiments of the invention]

FIG. 1 is an explanatory diagram showing one embodiment of the present invention, and FIG. 2 is a circuit diagram of the embodiment shown in FIG.
The same reference numerals as those in FIG. 4 indicate corresponding parts, and (1
6a), (16b), (15c), (16d), (16
e).

(16f) refers to a plurality of field-effect semiconductor elements in the integrated circuit shown in FIGS. 3 and 4 whose respective gates are connected to the same human input signal line and whose second electrodes are connected to the same potential point. These are field-effect semiconductor devices that are grouped together.

That is, by comparing FIG. 4 and FIG.
Since the gates of 5214 are connected to the same human input signal line and the second electrodes are connected to the same potential point, they can be combined into one element 16e. Similarly, the elements 5201 to 5204 can be combined into one element 16fK. To summarize like this, 5113 and 5114
, 8103 and 5104, 5ill and 8112°51
The gates of each pair of elements 01 and 5102 are connected to the same human input signal line, and the second electrodes are connected to the same potential point, so each element 16c is one element.

16d, 16b, and 16a. The gate width of these integrated devices is increased according to the number of original devices, and the on-resistance is lowered.

In the case of a decoding circuit that selects one of 2n output signal lines based on the signals of 2n input signal lines, even if the value of n becomes large, the connection between the output signal line and the power supply having the first potential is The sum of the on-resistances of the field-effect semiconductor elements between them does not exceed twice the on-resistance of the field-effect semiconductor element with the minimum gate width.

On the other hand, in the integrated circuit having the configuration shown in FIGS. 3 and 4, the sum of the on-resistances of the field effect semiconductor elements between the output signal line and the power supply having the first potential is one It is n times the on-resistance of a field effect semiconductor element (corresponding to the field effect semiconductor element with the above-mentioned minimum gate width).

As mentioned above, in the circuits with the configurations shown in FIGS. 1 and 2,
Even if the number of cascade-connected field-effect semiconductor devices increases, the sum of the on-resistances of the field-effect semiconductor devices between the output signal line and the power source with the first potential is the same as that of the field-effect semiconductor devices with the minimum gate width. Since it does not exceed twice the on-resistance of the element, the time from when the output signal line is connected to the power supply having the first potential until it reaches the first potential is not very long.

If the value of the load capacitance applied to the output signal line is smaller than the parasitic capacitance of the field effect semiconductor elements and wiring in the integrated circuit, this effect is small, but the load capacitance applied to the output signal line is When is large, the effect is large.

Note that the field effect semiconductor element may be of a p-type channel or of an n-type channel.

Further, the output signal line may be connected to a power supply having a second potential via a resistor, or may be connected to a circuit that precharges to the second potential, or may be connected to a channel of another type. The power source may be connected to a power source having a second potential via a field effect semiconductor element having a second electric potential.

〔Effect of the invention〕

As described above, according to the present invention, even if the number of cascade-connected field-effect semiconductor elements between the output signal line and the power supply having the first potential increases, the output signal line remains at the first potential. This has the effect that the time from when it is connected to a power source until it reaches the first potential is not too long.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention, FIG. 2 is a circuit diagram of the embodiment shown in FIG. 1, and FIG. 3 is an example of a conventional field-effect semiconductor element integrated circuit of this type. Explanatory diagram, 4th
The figure is a circuit diagram of the integrated circuit shown in FIG. 3. In the figure fl), +21, +31, +4
1, +51, +61 are input signal lines, +71,
+81, [91, (10), (11), (12)
, (13), (14) are output signal lines, (15) is a first potential section, (16), (16a). (16b), (16c), (16d), (16e), (
16f) is a field effect semiconductor element. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] A plurality of input signal lines are arranged in parallel, a plurality of output signal lines are arranged in parallel with each other in a direction perpendicular to the arrangement direction of the input signal lines, and the input signal A field-effect semiconductor element is provided at some of the intersections of the extension line of the output signal line and the extension line of the output signal line, and the gate of the field-effect semiconductor element is connected to one of the input signal lines. and each of the output signal lines is connected to a first electrode of one of the field effect semiconductor devices, and the second electrode of each field effect semiconductor device is connected to the device in cascade. A field effect semiconductor element integrated circuit connected to the first electrode of the next stage field effect semiconductor element to be connected, or connected to the first potential section in each element at the final stage of the cascade connection. In a circuit, a plurality of field-effect semiconductor elements whose gates are mutually connected to the same input signal line and whose second electrodes are mutually connected to the same potential point are collectively combined into one. 1. A field-effect semiconductor element integrated circuit, characterized in that it comprises two elements.