JPH01176390A - Memory card - Google Patents

Abstract

PURPOSE:To make a memory card high density and large quantity by arranging a static prevention element on the memory element of a substrate and on the other surface of the surface on which a terminal for external connection is arranged. CONSTITUTION:Memory elements 12a and 12b such as an RAM, an ROM for example, are mounted on one surface of a card substrate 11 and plural static prevention elements 16... of a chip resistance for example to prevent the flowing-in of a static electricity from each terminal for external connection 14 to the memory elements 12a and 12b are arranged at a position approximately confronting with each connection terminal land 15 on the other surface of the card substrate 11 surface where these memory elements 12a and 12b and the terminal for external connection 14 are arranged. Thus, without reducing a memory element mounting space on the substrate 1, the memory card of a static electricity flowing-in prevention type equipped with the static prevention element 16 can be constituted and a high density and large quantity of the memory card can be attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Field of Industrial Application) The present invention relates to a memory card that is used by being attached to an electronic device.

(Prior Art) In recent years, memory cards have become available, which are configured with a memory element on a card board, and when used by being attached to a predetermined electronic device, it is possible to write and output data to the memory element. It is commonly used.

This type of memory card is provided at its end with a plurality of external connection terminals that are connected to a connector provided on the electronic device side.

By the way, the memory elements built into the above-mentioned memory card are generally RAM, ROM, etc.
In particular, RAM is susceptible to damage caused by static electricity.
If static electricity flows into the device through the external connection terminal,
There was a risk that the memory contents would be destroyed.

For this reason, recently, resistors have been connected between each external connection terminal and the memory element, and Zener diodes and capacitors have been connected in parallel between the power supply terminal and the common terminal of each external connection terminal. A method is used to prevent static electricity from flowing into the memory element.

One example is Utility Model Application No. 59-4095
There are some disclosed in Publication No. 5 and the like. This is the third
This will be explained based on the diagram.

FIG. 3 is a perspective view showing a two-piece connector type memory card.

In the figure, 1 indicates a card board. On this card board 1, there are memory elements 2a, 2b and an electronic device bag π.
A plurality of external connection terminals 4 are connected to the connector 3 of
and a plurality of anti-static elements 5, such as chip resistors, for preventing the inflow of static electricity from each external connection terminal 4 to the memory elements 2a, 2b, respectively, through conductor wiring 6. It is arranged as follows.

That is, in this memory card, antistatic elements 5 are connected in series on each conductor wiring 5 between each external connection terminal 4 and the memory elements 2a and 2b. This prevents static electricity from flowing from the external connection terminal 4 into the memory elements 2a, 2b.

(Problems to be Solved by the Invention) However, the above-mentioned memory card requires a dedicated space on the card board for arranging the same number of antistatic elements as the number of external connection terminals. For example, if a chip resistor with a length of 2ni and a width of 1.25u is used as an antistatic element, the length will be about 4n if lands for soldering external connection terminals are included.

As described above, when the antistatic element is disposed on the card substrate, there is a problem in that the mounting space of the memory element is compressed, which hinders the increase in the density and capacity of the memory card.

The present invention is intended to solve these problems, and can be implemented without reducing the space for mounting memory elements on the board.
An object of the present invention is to provide a memory card that can be configured as a static electricity flow prevention type memory card equipped with an antistatic element, and that can increase the density and capacity of the memory card.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention includes a memory element on a substrate and electrical connection to the memory element via an antistatic element. A memory card having a plurality of external connection terminals disposed thereon, wherein an antistatic element is disposed on the other side of the substrate on which the memory element and external connection terminals are disposed. It is something.

(Function) In the memory card of the present invention, the antistatic element is disposed on the other side of the board on which the memory element and external connection terminals are arranged, so the space for mounting the memory element on the board is reduced. It is possible to construct a static electricity prevention type memory card equipped with an antistatic element without causing any damage, and it is possible to increase the density and capacity of the memory card.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 1 is a plan view showing the structure of a memory card as an example of the present invention, and FIG. 2 is a sectional view of the memory card of FIG. 1.

In these figures, 11 indicates a card board.

Memory elements 12a and 12b, such as RAM and ROM, are mounted on one side of the card board 11, and the end thereof is connected to a connector 13 of an electronic device (not shown). Multiple external connection terminals 1
4 are connected to the connection terminal lands 15 by soldering, respectively.

Further, on the other side of the card board 11 on which the memory elements 12a, 12b and the external connection terminal 14 are arranged, the memory elements 12a, 12 are connected from each external connection terminal 14.
A plurality of antistatic elements 16, such as chip resistors, for preventing static electricity from flowing into the connecting terminal lands 15 are disposed at positions substantially facing each connecting terminal land 15.

Furthermore, the memory elements 12a, 12b, the external connection terminals 14, and the antistatic element 16 are connected to each other via conductor wiring 17 printed on both sides of the card board 11 and through poles 18 of the card board 11. each connected.

Further, on this card board 11, a backup power source for the memory element, a ground, etc., which are not shown, are arranged.

Thus, according to the memory card of this embodiment, the memory elements 12a, 12b and the external connection terminal 14 are arranged on one side of the card substrate 11, and the antistatic element 16
are arranged on the other side of the card board 11 via the through hole 18, so that the memory elements 12a, 12b (especially , it is possible to configure a memory card that prevents static electricity from flowing into the RAM 12a).

For example, the size of a memory card is 86++I x 54m.
m, the mounting area of the antistatic element 16 is approximately 216u2
Can be reduced.

Therefore, it is possible to effectively increase the density and capacity of the memory card.

Although this embodiment has been explained using a so-called two-piece connector type memory card as an example, the present invention can be similarly applied to a card edge type memory card by using a printed resistor or the like as an antistatic element. can.

Further, in this embodiment, a RAM is used as the memory element, but an EEF ROM may be used similarly.

In this case, there is no need to incorporate a backup power source into the memory card.

[Effects of the Invention] As explained above, according to the memory card of the present invention, the memory element mounting space on the board can be reduced without reducing the memory element mounting space.
It is possible to configure a static electricity flow prevention type memory card equipped with an antistatic element, and it is possible to increase the density and capacity of the memory card.

[Brief explanation of the drawing]

FIG. 1 is a plan view for explaining the structure of a memory card according to an embodiment of the present invention, FIG. 2 is a sectional view of FIG. 1, and FIG. 3 is a perspective view for explaining the structure of a conventional memory card. It is a diagram. DESCRIPTION OF SYMBOLS 11... Card board, 12a, 12b... Memory element, 14... Terminal for external connection, 16... Antistatic element, 17... Conductor wiring, 18... Through hole. Figure 3

Claims (1)

[Claims] (1) A memory card in which a memory element and a plurality of external connection terminals electrically connected to the memory element via an antistatic element are arranged on a substrate,
A memory card characterized in that the antistatic element is disposed on the other surface of the substrate on which the memory element and the external connection terminal are disposed.