JPH07221257A - Electronic component having terminal array - Google Patents

Abstract

PURPOSE:To enhance reliability when leads are drawn out of IC terminals of fine pitch by making terminals cause no particular problem even in electric short circuit adjacent to general-purpose input/output terminals. CONSTITUTION:If terminals 60 and 63 are terminals MONs 1 and 2 to draw out, a terminal 61 that is a vacant terminal NC is arranged adjacent to the terminal 60, and a terminal 69 that is an open drain terminal or open collector terminal OP adjacent to the terminal 63. In the case of drawing a lead out of the terminal 63, both terminals 63 and 64 are soldered together with the terminal 64 floated, and the lead is drawn out. This makes it easier to work than in drawing a lead out of one terminal because a lead is drawn out of a soldered point of two terminals in the case where the gap of terminals is fine 0.5mm pitch, so that reliability improves.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component having a terminal arrangement such as an IC.

[0002]

2. Description of the Related Art When designing a custom IC, terminals are provided on the outer periphery of the IC in order to exchange signals with the outside. At this time, the first thing to note is the separation of analog and digital signals. These two signals are
It is usual to arrange the ICs so that they do not interfere with each other when they leave the IC on the printed wiring board. Also, IC
The direction in which signals are taken out may be limited due to the convenience of mounting the on a printed wiring board. In such a case, it is important to arrange the terminals according to the direction in which the signal is taken out.

As described above, conventionally, the arrangement of terminals has been determined in consideration of the separation of analog signals and digital signals and the direction of taking out signals.

[0004]

The high-density mounting of electric circuits makes it possible to downsize the product and improve portability. However, as the density is increased, there is no room for human manual labor in the manufacturing process. In particular, when designing and prototyping proceed at the same time, it may be more efficient to add a temporary circuit during prototyping, monitor signals for circuit examination, or perform manual work by humans.

In this case, what is most done is to use a conductor exposed portion on the substrate to output a signal to the outside through a lead wire, but such a conductor exposed portion is often not present on the substrate. In this case, the signal is directly taken out from the terminal of a large number of custom ICs for signals, but in recent years, it has become difficult to lead the wires manually by human due to the remarkable fine pitch of the custom IC.

On the other hand, when developing a custom IC, it is rare to use all the pins prepared in the package, and in many cases there are empty terminals. Therefore, general-purpose ports are also assigned to empty pins.
However, when assigning this empty pin to a general-purpose port, if the pattern of the printed wiring board on which the custom IC is mounted does not correspond to the general-purpose port, it becomes difficult to use.

Further, when it is desired to monitor the signal of a certain terminal for inspection, the signal is directly taken out from the terminal by a lead wire or the like. However, due to the recent progress in high-density mounting, the distance between terminals is becoming as small as 0.5 mm pitch, so even if a skilled worker works, it is difficult to derive a lead wire from the target terminal by soldering. There is a problem that it is difficult, and reliability is lacking even if possible.

The present invention has been made in view of such circumstances, and it is an object of the present invention to improve the reliability in leading a lead wire from an IC terminal having a fine pitch.

[0009]

To achieve the above object, the present invention has a plurality of linearly arranged terminals, of which terminals that can be in a floating state and general-purpose input / output terminals. Are arranged next to each other.

[0010]

In the electronic component having the above-described terminal arrangement, the general-purpose input / output terminal and the terminal that can be in a floating state, that is, a state in which no particular problem occurs even when electrically short-circuited, are adjacent to each other When a signal is output to the outside by a lead wire, two adjacent terminals can be soldered together to enhance the reliability when the lead wire is led out from the fine pitch IC terminals.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a top view showing an embodiment of an electronic component having a terminal arrangement according to the present invention. FIG. 2 is a top view showing an electronic component having a conventional terminal arrangement shown for comparison.

In FIG. 1, the IC 11 is a 64-pin Q
FP (QUAD FLAT PACKAGE) IC, and Fig. 1 shows IC1
Only part of 1 (upper right part) is shown. The IC 11 has a substantially rectangular shape, and terminals 1 to 64 are provided on the outer peripheral portion thereof. However, only terminals 1 to 6 and terminals 60 to 64 are shown in FIG.

The terminal 60 is a terminal (MON2) which is desired to be output by a lead wire to the outside. The terminal 61 is an empty terminal (a terminal that is not connected to the inside, NC). The terminal 62 is another terminal (OT), for example, a terminal from which a CMOS output is taken out. The terminal 63 is a terminal (MON1) to be output to the outside by a lead wire. The terminal 64 is an open drain terminal or an open collector terminal (OP).

Thus, the terminals 60 and 63 are
The terminal you want to output to the outside with a lead wire (general-purpose input / output terminal, MO
N1 and MON2), a terminal 61, which is an empty terminal (a terminal not connected to the inside, NC), is arranged next to the terminal 60. Next to the terminal 63, an open drain terminal or an open collector terminal (O
The terminal 64 which is P) is arranged. The terminal 62 is another terminal (OT).

When the lead wire is taken out from the terminal 63, the terminal 64 is left in a floating state, both terminals 63 and 64 are soldered together, and then the lead wire is taken out. When the terminal spacing is as small as 0.5 mm pitch, it is easier to work the lead wire from the location where the two terminals are attached, as compared to the one terminal. Yes Improves reliability.

Also in FIG. 2 (conventional example) shown for comparison, the IC 101 is a 64-pin QFP (QUAD FLAT PACK).
AGE) IC, and FIG. 2 shows only a part of IC 101 (upper right part). The IC 101 has a substantially rectangular shape, and terminals 1 to 64 are provided on the outer peripheral portion thereof. However, only terminals 1 to 6 and terminals 60 to 64 are shown in FIG.

The terminal 60 is a terminal (MON4) which is desired to be output to the outside by a lead wire. Terminal 61 is the other terminal (O
T), which is a terminal from which a CMOS output is taken out, for example. The terminal 62 is a terminal (M
ON3). The terminal 63 is another terminal (OT), for example, a terminal from which a CMOS output is taken out.
The terminal 64 is an empty terminal (terminal not connected to the inside,
NC).

Conventionally, as shown in FIG. 2, taking out a lead wire from the terminal is not considered, and the terminal 62 (M
Even when the lead wire is output from (ON3), the terminal 61 or 63 does not become in a floating state, so if they are attached together, a large current may flow into the internal circuit of the IC 101, resulting in damage. That is, conventionally, the only method is to lead the wire from one terminal.

The floating state in this specification means a state in which the electrical impedance is very high and there is no effect even when connected to other electric circuits. Hereinafter, the floating state will be described with reference to FIGS. 3 and 1.

FIG. 3A shows a state in which the terminal 64 is in a floating state (high impedance). When the inside of the IC 11 is shown by an equivalent circuit, the terminal 64 is connected to the GND (ground) terminal via the switch SW, and the switch SW is in an off state. Switch SW
As shown in FIG. 1, is a changeover switch whose on / off changeover control is performed by signals supplied to terminals C1 to C4. The terminal 64 is connected to the power supply by the pull-up resistor R. The pull-up resistor R may be connected in series with a light emitting diode (not shown). When the terminal 64 is in a floating state, the terminal 64 is at a high level, so that the light emitting diode (not shown) connected in series to the pull-up resistor R is turned off.

FIG. 3B shows a state in which the terminal 64 is no longer in the floating state. The switch SW is turned on, and the terminal 64 has a ground potential (low level,
Low impedance). When the terminal 64 becomes the ground potential, a current flows through the pull-up resistor R, and a light emitting diode (not shown) connected in series with the pull-up resistor R lights up. In this way, a terminal that can switch between a floating state (high impedance) and a low impedance is a terminal that can be in a floating state.

The present invention has been described above with reference to the embodiments.
Various modifications are possible according to the technical idea of the present invention. For example, in the above-described embodiment, the terminal 64 that can be in the floating state is arranged only next to one of the terminals 63 that are general-purpose input / output terminals, but the other terminal 62 is also a terminal that can be in the floating state. It is also possible to arrange terminals that can be in a floating state on both sides of the input / output terminal. In this case, since it is allowed to attach the three terminals together, the work is further facilitated and the reliability is further improved.

Further, in the above-described embodiment, the case where the electronic component is a custom IC has been described, but the present invention can be applied to an electronic component other than the custom IC.

Further, in the above-described embodiment, the case of soldering together is explained, but with the electronic component according to the present invention, even when the probe is brought into contact with the terminal, the signal can be extracted with higher reliability. be able to. Further, in the above-described embodiment, the terminal that can be in the floating state is described as if it is the output terminal.
It may be a terminal that can be an input terminal.

[0026]

As described above, according to the present invention, the terminal which can be in the floating state, that is, the state in which no particular problem occurs even when electrically short-circuited, and the general-purpose input / output terminal are adjacent to each other. When sending a signal to the outside with a lead wire,
By soldering two adjacent terminals together, it is possible to increase the reliability when leading out a lead wire from an IC terminal with a fine pitch.

[Brief description of drawings]

FIG. 1 is a top view showing an embodiment of an electronic component having a terminal arrangement according to the present invention.

FIG. 2 is a top view showing an example of an electronic component having a conventional terminal arrangement.

FIG. 3 is an equivalent circuit diagram illustrating an embodiment of an electronic component having a terminal arrangement according to the present invention.

[Explanation of symbols]

 1 to 6 terminals 11 IC 60 to 64 terminals

Claims (6)

[Claims] 1. A plurality of terminals linearly arranged at a fine pitch, wherein a terminal that can be in a floating state and a general-purpose input / output terminal are arranged next to each other. An electronic component having a terminal arrangement. 2. An electronic component having a terminal arrangement according to claim 1, wherein the arrangement pitch of the terminals is 0.5 mm pitch. 3. The electronic component according to claim 1, wherein the terminal that can be in a floating state is an open collector terminal. 4. The electronic component according to claim 1, wherein the terminal that can be in a floating state is an open drain terminal. 5. The electronic component according to claim 1, wherein the terminal that can be in a floating state is an empty terminal. 6. An electronic component having a terminal arrangement according to claim 1, wherein the terminal that can be in a floating state is a terminal that can be an input terminal.