JP3179211B2 - Semiconductor integrated circuit device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor integrated circuit device of an analog circuit, and more particularly to a configuration of a functional block used for automatic placement and routing by a computer.

[0002]

2. Description of the Related Art In recent large-scale analog integrated circuits, in order to shorten the design period and standardize the design, several tens of circuit elements are used as one functional block unit, and the arrangement and wiring of each functional block are performed by a computer. Is going. As shown in FIG. 3, a conventional functional block used for such automatic placement and routing includes a power supply wiring formed on the upper side and the bottom side of a functional block frame 1A, which is a rectangular area, a part of which is formed by the same metal wiring layer as an element electrode. VCC and ground wiring GND are provided. External terminals 11 are provided at both ends of these wirings, respectively.
To 14 are provided. The layout design in the functional block is based on transistors Q1 to Q1 corresponding to the desired circuit element.
Q6, the resistors R1 to R4, and the like are selected, and the arrangement of the elements and the wiring by the element wiring 2 are performed so as to fit in a predetermined rectangular area of the functional block frame 1A. FIG. 2 shows an equivalent circuit of a circuit constituted by the functional blocks.

[0003]

In such a conventional semiconductor integrated circuit device, the emitter wirings of the transistors Q1 and Q2 forming the current mirror circuit are connected so as to have a common impedance to the power supply wiring. However, since each emitter wiring is individually connected to a different position of the power supply wiring GND, when another functional block is connected to this functional block, each emitter wiring is caused by the current of the other functional block. A difference may occur in the current of the wiring, and the matching between elements may be degraded.

When a semiconductor integrated circuit device 10 in which a plurality of functional blocks A to G are arranged and a power supply wiring VCC and a ground wiring GND are connected as shown in FIG. The total value of the current is limited by the wiring width of the functional blocks A and D closest to the bonding pad PD. Therefore, when the current capacity of the ground wiring is insufficient in the functional blocks A and D, the ground wiring 1 in FIG.
It is necessary to change the design such as increasing the minimum width of the wiring 2 (in this example, the width of the two-layer wiring 3 connecting the ground wiring GND with the through hole 4 in the middle) or the ground wiring of the functional block A. As in the case of GND, wiring is performed to the vicinity of the bonding pad alone, which has been a factor of increasing the wiring area. SUMMARY OF THE INVENTION An object of the present invention is to provide a semiconductor integrated circuit device capable of preventing deterioration of matching between elements in a functional block and reducing a wiring area in a power supply and a ground wiring.

[0005]

SUMMARY OF THE INVENTION The present invention comprises a plurality of functions.
In a semiconductor integrated circuit device in which blocks are arranged , a power supply wiring to a functional block and first and second transistors in the functional block and having a base commonly constituting a current mirror circuit are commonly connected. A wiring connecting the first transistor and the power supply wiring and a wiring connecting the second transistor and the power supply wiring are united so as to have a common impedance with respect to the power supply wiring. The power supply line is connected at one point.

[0006]

Next, the present invention will be described with reference to the drawings. FIG. 1 is a plan view of a functional block according to an embodiment of the present invention.
FIG. 2 is an equivalent circuit diagram. In FIG. 1, PNP transistors Q1, Q2
And NPN transistors Q3 to Q6 and resistors R1 to
R4 is arranged. Further, a power supply line VCC and a ground line GND are linearly arranged above and below the functional block frame 1, respectively. The elements are connected to each other by an element wiring 2 to form the equivalent circuit of FIG. 2. The element wiring 2 uses the same metal wiring layer as the power supply wiring VCC and the ground wiring GND. In some cases, a two-layer metal wiring is used depending on the circuit configuration. The power supply line VCC
And external terminals 11, 1 at both ends of the ground wiring GND, respectively.
2 and 13 and 14 are provided.

Here, the PNP transistors Q1, Q
2 constitutes a current mirror circuit in the circuit of FIG. 2. The transistors Q1 and Q2 are arranged adjacent to each other. The power supply line connected to the emitter of each transistor is connected to the element wiring 2 together with the power supply end of the resistor R1. It is connected to the power supply line VCC at one point between the external terminals 11 and 12. Also, the ground terminals of the resistors R2 to R4 are united by the same element wiring 2 and the external terminal 1 of the ground wiring GND is connected at one point via the through hole 4 and the two-layer metal wiring 3.
It is connected between 3 and 14.

Therefore, since the transistors Q1 and Q2 forming the current mirror circuit have the emitter wiring connected to the power supply wiring VCC at one point by the element wiring 2, the currents of the other functional blocks are independent of the arrangement of the functional blocks. Is not degraded. Further, since the power supply wiring VCC and the ground wiring GND have a linear shape, the wiring width can be arbitrarily increased toward the outside of the functional block, and wiring design such as electric capacity becomes easy.

[0009]

As described above, according to the present invention, a plurality of
In a semiconductor integrated circuit device in which functional blocks are arranged,
A power supply line to a functional block; and a first transistor and a second transistor in the functional block, the bases of which constitute a current mirror circuit, commonly connected, and the first transistor and the power supply A wiring connecting to the wiring and a wiring connecting the second transistor and the power supply wiring are united so as to have a common impedance with respect to the power supply wiring, and are connected to the power supply wiring by one.
Because they are connected at points, regardless of the arrangement of the functional blocks, the deterioration of the consistency due to the current of other functional blocks is improved, and even if the width of the power supply wiring is arbitrarily expanded to the outside of the functional blocks, Since the capacitance can be increased, it is possible to obtain an effect that the design of the wiring is facilitated and the diversion of the functional blocks is also improved.

[Brief description of the drawings]

FIG. 1 is a functional block plan view of one embodiment of a semiconductor integrated circuit device of the present invention.

FIG. 2 is an equivalent circuit diagram of the circuits of FIGS. 1 and 3.

FIG. 3 is a plan view of a functional block of a conventional semiconductor integrated circuit device.

FIG. 4 is a schematic layout diagram of a semiconductor integrated circuit device constituted by conventional functional blocks.

[Explanation of symbols]

 Reference Signs List 1 functional block 2 element wiring 3 two-layer wiring 4 through hole Q1-Q6 transistor R1-R4 resistance VCC power supply wiring GND ground wiring

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01L 21/3205 H01L 21/82

Claims (1)

(57) [Claims] 1. A semiconductor in which a plurality of functional blocks are arranged.
In an integrated circuit device, power supply wiring to a functional block;
A first transistor and a second transistor in which the bases constituting the current mirror circuit in the functional block are commonly connected, and a wiring connecting the first transistor and the power supply wiring; A semiconductor, wherein a wiring connecting the second transistor and the power wiring is united so as to have a common impedance with respect to the power wiring, and is connected to the power wiring at one point. Integrated circuit device.