| 摘要 |
<p>PURPOSE:To prevent the data from being written erroneously in the card in the case a supply voltage to the card side drops suddenly by inserting a unidirectional switch element between a power source line and a control terminal. CONSTITUTION:Between a power source line 3 and a control terminal C of a card side 2, a unidirectional switch element 6 is inserted in the forward direction against the power source line 3. In such a state, in the case a supply voltage to the card side 2 drops suddenly by drawing out the card, etc., it is prevented by the unidirectional switch element 6 that a reverse current flows in the direction of the power source line 3 from the control terminal C of a memory 5. Therefore, the level of a control signal Sc in the control terminal C remain 'H' for a while. In such a way, it is prevented that a system bus, etc., are broken down due to a bus fight by which data is written erroneously in the card.</p> |
