JP2569617B2 - Integrated circuit device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrated circuit device, and more particularly, to a method of terminating an integrated circuit device requiring a terminating resistor in a circuit by using a resistance element.

[Prior Art] Conventionally, for input / output terminals of this type of integrated circuit device requiring termination by a resistor, a resistor component independent of the integrated circuit device is installed on a substrate on which the integrated circuit device is mounted, Is connected to the input / output terminal of the integrated circuit by wiring.

The reason for connecting such discrete resistance components is that it is necessary to match the resistance value of the terminating resistor itself with the impedance of the transmission line on the substrate on which it is mounted, and therefore extremely high precision resistance values are required. Incorporating such a resistor into the device causes a reduction in manufacturing yield, resulting in a very high price.

For this reason, the terminal that requires the terminating resistor of the integrated circuit device itself is configured as an unterminated terminal as the integrated circuit device.

[Problems to be Solved by the Invention] Although the input / output terminals of the above-described conventional integrated circuit device requiring resistor termination are in an unterminated state, in recent years, the density of integrated circuit devices has increased, A large-scale integrated circuit and the like are mounted on a substrate on which the device is mounted, and other mounted components such as capacitors are decreasing year by year. Among them, this kind of terminating resistor is left as a single component, which has a drawback that it is a great hindrance in increasing the mounting density on a mounting board.

On the other hand, if this type of resistor is formed on a monolithic integrated circuit chip in the same manner as other resistive elements, the required accuracy of this type is extremely severe as described above, which lowers the manufacturing yield and consequently lowers the product cost. It has the disadvantage that it rises significantly.

[Differences of the Invention from the Prior Art] As described above, in the conventional integrated circuit device, since the input / output terminals that require the resistive termination in the integrated circuit device are unterminated, a terminating resistor is installed on the mounting board of the device. On the other hand, in the present invention, since the terminating resistor is prepared in the integrated circuit device in advance, it is not necessary to particularly install the terminating resistor on the mounting board of the device. The difference is that implementation is feasible.

[Means for Solving the Problems] The gist of the present invention is an integrated circuit device in which a monolithic integrated circuit chip and a resistance element are mounted on one package base, and one end of the resistance element is provided inside the package base. The other end of the resistance element is connected to a first external lead outside the package base to which a terminal potential is applied via an internal lead, and the other end of the resistive element is connected to the monolithic via a second external lead outside the package base. It is connected to pads on an integrated circuit chip as needed.

Embodiment 1 Embodiment 1 FIG. 1 is a partially enlarged plan view inside a package according to an embodiment of the present invention. Monolithic integrated circuit chip 1 (hereinafter LS)
The pad 1A disposed on the I chip) is an ECL input pad, the pad 2A is an ECL output pad, and the pad 3A is an output termination potential supply power supply pad inside the LSI chip 1. This LSI chip 1 is mounted in a package. Pad 1A is connected to internal lead 1C of the package, pad 2A is connected to internal lead 2C of the package, pad 3A is connected to internal lead 3C of the package, and TAB leads 1B, 2B, 3B are connected to internal lead 3C of the package. Connected to each other. In this embodiment, the LSI chip 1
The package interlayer insulating film 3 is interposed immediately outside the internal lead connected by the TAB lead to provide independent internal leads. The internal leads 1D, 2D, and 3D shown in FIG. 1 correspond thereto. The internal leads 1D, 2D, and 3D are terminating resistors 1E, 2E, and 3E similarly formed of a metal thin film on the package interlayer insulating film 3.
Are connected to one terminal of
The other terminals of 1E, 2E, 3E are commonly connected by wiring 6.

This package has a multi-layer wiring structure, and internal leads
1C is connected to the wiring 1F and to the external lead 1G of the package. The internal lead 2C is connected to the wiring 2F, and is connected to the external lead 2G of the package. Internal lead 3C is wiring 3F
To the external lead 3G of the package.
Since the output terminal potential inside the LSI chip 1 is assumed to be the same as the output terminal potential of the present integrated circuit device, the wiring 6 is also connected to the wiring 3F, and as a result, the wiring 6 is connected to the external lead 3G of the package. Have been.

The ECL circuit usually has a termination resistor of 50Ω for each output terminal. However, due to the reflection of the transmission wiring on the board on which the integrated circuit device is mounted, the input terminal section farthest from the corresponding output is actually used. In many cases, a terminal resistor is installed. Therefore, also in this embodiment, the pad 2A which is the ECL output
No termination resistor is added, the internal lead 1C and the internal lead 1D, which are connected to the pad 1A to be the ECL input, are connected with the bonding wire 5 and the ECL output terminal connected to the external lead 1G on the mounting board A resistor is added at the input terminal.

In this embodiment, the wiring 6 is provided immediately outside the internal leads 1C, 2C, 3C of the package directly connected to 1A, 2A, 3A on the LSI chip.
The internal leads 1D, 2D, and 3D that are connected to each other terminal of each of the 50Ω terminating resistors 1E, 2E, and 3E that commonly connect one terminal are provided only for input / output terminals that require the addition of a terminating resistor. By connecting the inner inner lead and the outer inner lead with a bonding wire, a terminating resistor can be added.

In this case, the terminating resistor is formed of a metal thin film on the package body, but the precision required for the terminating resistor of the ECL circuit is extremely high, about 50Ω ± 1% or ± 0.1%. Since it is extremely difficult to achieve this accuracy at the time of initial formation, the metal thin film resistor on this type of package is trimmed with a laser or the like to meet the required accuracy after formation, and the desired termination resistance value is obtained. I do.

Embodiment 2 FIG. 2 is a partially enlarged plan view of the inside of a package according to a second embodiment of the present invention. When a plurality of the same integrated circuit devices are mounted on a mounting substrate, even if it is necessary to add a terminating resistor at one input terminal portion of the first integrated circuit device, the same input terminal portion of the second integrated circuit device may be used. It is often the case that terminating resistors are not needed. FIG. 2 shows an example in which a termination resistor is provided on a package irrespective of pads on an LSI chip. 4A, 5A and 6A on the LSI chip 7 mounted in the package are the internal leads 4C, 5C and 6C of the package, respectively.
Are connected by bonding wires 4B, 5B, 6B to
The internal leads 4C, 5C, 6C are connected to the external leads 4E, 5E, 6E of the package by wirings 4D, 5D, 6D, respectively. In this case, all of the pads 4A, 5A, and 6A are pads for ECL input. External leads 4E and 5 to be ECL input terminals in this case
For E and 6E, no terminating resistor is added.

This package contains a terminal resistor 10 made of a thin metal film.
Is provided. One terminal of the terminating resistor 10 is drawn out by a wiring 7C and connected to an external lead 7E of the package through a wiring 7D. The other terminal of the terminating resistor 10 is drawn out by a wiring 8C and is connected to an external lead 8E of the package through a wiring 8D. The terminating resistor 10 is also formed as a resistor of about 50Ω which does not satisfy the required required accuracy when it is formed in advance. However, the required accuracy is set to ± 1.0% or ± 0.1% by a trimming process using a laser or the like.

In the case of an ECL circuit, the output terminating resistor is often provided at the input terminal section of the load at the farthest end depending on the integrated circuit device having its output, so that one integrated circuit device corresponds to all inputs and outputs It is not necessary to prepare a high-precision resistor for each external lead, and it is only necessary that a terminal resistor can be added by wiring connection on a mounting substrate as needed, such as an input terminal that needs to be added. In FIG. 2, when the terminating resistor 10 is required for the external lead 4E, the external lead 4E and the external lead 8E are connected by wiring on the mounting board,
The external lead 7E may be connected to a terminal potential power supply.

[Effect of the Invention] As described above, the present invention relates to an integrated circuit device equipped with a single monolithic integrated circuit chip, in which a circuit termination resistor element is formed in a package body of the integrated circuit device, and the circuit termination resistor is formed. Since one terminal of the resistance element is connected to the first external lead of the package and the other terminal is connected to the second external lead of the package, a single resistor serving as a terminating resistor from the substrate on which the integrated circuit device is mounted The components can be removed, and as a result, the mounting density of the components on the substrate is increased, and there is an effect that the size of the device can be reduced.

In the embodiment of the present invention, the case of the terminating resistor of 50Ω for the ECL circuit is discussed, but it goes without saying that the same effect can be obtained even when applied to other terminating resistors such as a pull-up resistor of a TTL circuit. .

[Brief description of the drawings]

FIG. 1 is a partially enlarged plan view inside a package showing a first embodiment of the present invention, and FIG. 2 is a partially enlarged plan view inside a package which is a second embodiment of the present invention. 1,7 …… LSI chip, 2,3,4,8,9 …… Package interlayer insulating film, 5,4B, 5B, 6B …… Bonding wire, 6,1F, 2F, 3F, 7C, 8C, 4D, 5D, 6D, 7D, 8D …… Wiring, 1A, 2A, 3A, 4A, 5A, 6A …… Pad, 1B, 2B, 3B …… TAB lead, 1C, 2C, 3C, 1D, 2D, 3D, 4C, 5C, 6C …… Internal lead, 10,1E, 2E, 3E …… Terminal resistor, 1G, 2G, 3G, 4E, 5E, 6E, 7E, 8E …… External lead.

Claims (1)

(57) [Claims] 1. An integrated circuit device having a monolithic integrated circuit chip and a resistance element mounted on a single package base, wherein one end of the resistance element is supplied with a terminal potential via an internal lead in the package base. The other end of the resistive element is connected to a first external lead outside the package base, and the other end of the resistance element is connected to a pad on the monolithic integrated circuit chip via a bonding wire or a second external lead outside the package base, if necessary. Integrated circuit device connected