| 摘要 |
PURPOSE:To attain simultaneously an operation test under the operating conditions of a bubble memory device and a test under information holding conditions by writing information under the operating conditions, changing peripheral conditions temporally in the range of the information holding conditions, then returning the condition to the operating conditions to read out the information and detect a defective loop. CONSTITUTION:A driving magnetic field and a bias magnetic field are applied to the range of the operating conditions of a bubble memory device from which a defective loop is to be detected, i.e. the condition of one point A of a block 21, to write information in a minor loop 13 of the device. The conditions of the bias magnetic field is temporally changed to the condition of a point B in the range of the information holding conditions and the condition is returned to the condition in the operating conditions to read out the information and compares the read information with written information. If an error is detected, the minor loop in which the information is written is regarded as a defective loop. Consequently, the operation test under the operating conditions of the bubble memory device and the test under the information holding conditions can be attained simultaneously. |
