JPH03212789A - Ic card system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to 1. a C card system used in external storage media of computers and the like.

[Conventional technology]

FIG. 2 is a block diagram showing signal exchange in a conventional IC card system. In the figure, (1) is the CPU (Central Process) on the external device side.
(2) is an interface circuit on the external device side, (3) is a connection terminal for electrically and physically connecting the IC card and the external device, and (4) is a terminal for storing information. The memory section (5) is an interface circuit on the IC card side.

Next, the operation will be explained.

When trying to write information on the IC card side, the data is sent from the external device's CPU (1) to the interface circuit (2) on the external device side and the memory section (4) on the IC card side via the connection terminal (3). Information is stored in.

When trying to read certain information from the IC card side,
From the C-P U (1) on the external device side to the ingoo face circuit (2) on the external device side and the IC via the connection terminal (3)
A command to read information is transmitted to the memory section (4) on the card side, and in response, the memory section (4) on the IC card side j9
Information is transmitted to the external device side via the interface circuit (5) and connection terminal (3) on the IC card side.

[Problem to be solved by the invention E] Since the conventional IC card system is configured as described above, there is no particular temperature control inside the IC card, and the system operates even when the temperature inside the IC card rises abnormally. However, there were problems such as access time delay, access timing mismatch, increased current, and abnormal operation of the C card.

This invention was made to solve the above-mentioned problems, and it provides an IC card system that can stop operation when the temperature rises abnormally by monitoring the temperature inside the IC card. With the goal.

[Failure to solve the problem]

The IC card system according to the present invention detects an abnormal temperature rise inside the IC card and notifies the external device of the abnormal temperature rise, thereby stopping information access from the external device.

[Effect]

The IC card system according to the present invention monitors the temperature inside the card using a temperature sensor installed inside the IC card, and when the temperature inside the IC card reaches a predetermined temperature, the IC card system sends a signal to an external device side of the IC card system. A signal is sent to stop access to the engineering C card from external devices.

〔Example〕

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

FIG. 1 is a block diagram of the RIC card system.

In the figure, (1) to (5) are the same as those shown in the conventional example of FIG. 2, and therefore their explanation will be omitted. (11) is a temperature sensor, and (12) is a detection circuit that detects a signal from the temperature sensor (11).Next, the operation will be explained.

When attempting to write certain information to the IC card side, the CPU (1) on the external device M side passes through the interface circuit (2) on the external device side and the connection terminal (3) to the memory section (4) on the IC card side. ) information is stored.

Also, when attempting to read certain information from the IC card side, the CPU (1) on the external device side reads the information from the IC card side via the interface circuit (2) and connection terminal (3) on the external device side. A command to read information is transmitted to the memory unit (4) of the IC card, and in response, the memory unit (4) of the IC card side
), information is transmitted to the external device side via the interface circuit (5) and connection terminal (3) on the C card side.

Furthermore, the operating temperature of the IC card is set to a certain temperature, and when the IC card internal temperature reaches that temperature,
The detection circuit (1) is detected by the temperature sensor (11) inside the IC card.
2), and the signal is transmitted to the CPU (1) on the external device side via the connection terminal (3).

c P [T (1) on the external device side receives the signal and stops accessing the IC card (111).In the above embodiment, the temperature sensor (11) is used for temperature detection, but A shape memory alloy equipped with a reset mechanism may be used, or an IP thermometer may be used. [Effects of the Invention] As described above, according to the present invention, Since the structure is configured such that access to the IC card from the external device side can be stopped when the temperature rises to normal, abnormal operation of the RC card can be prevented, and a highly reliable IC card system can be provided.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an IC card system according to an embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional IC card system. In the figure, (1) is CPU, (2), (5)
is an interface circuit, (3) is a connection terminal, (4) is a memory section, (11) is a temperature sensor, and (12) is a detection circuit. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] An IC card that includes a semiconductor memory element, a semiconductor memory element control circuit, and an external connection terminal for electrically and physically connecting to an external device, and exchanges information through this IC card and the external connection terminal. An IC card system comprising an external device that performs the above operations, characterized by having a function of stopping access to the IC card from the external device when the internal temperature of the IC card reaches a certain predetermined temperature. IC card system.