Abstract: A diagnostic device which can measure quickly and has simple circuit is provided. A charge/discharge circuit 2 supplies charge current to a rechargeable battery 10 and discharges the rechargeable battery 10. The charge/discharge circuit 2 also breaks charge current or discharge current of the rechargeable battery 10 in charging or discharging. A voltage measurement part 6 measures terminal voltage of the rechargeable battery 10 after breaking the charge or discharge current. Diagnostic means 8 judges whether the rechargeable battery 10 is deteriorated or not based on the measured voltages. Voltage change of deteriorated rechargeable battery 10 after breaking the charge or discharge current is more rapid than that of healthy rechargeable battery 10. The diagnostic means 8 can judge whether the rechargeable battery 10 is deteriorated or not based on such voltage change.

Abstract: A diagnostic device which can measure quickly and has simple circuit is provided. A charge/discharge circuit 2 supplies charge current to a rechargeable battery 10 and discharges the rechargeable battery 10. The charge/discharge circuit 2 also breaks charge current or discharge current of the rechargeable battery 10 in charging or discharging. A voltage measurement part 6 measures terminal voltage of the rechargeable battery 10 after breaking the charge or discharge current. Diagnostic means 8 judges whether the rechargeable battery 10 is deteriorated or not based on the measured voltages. Voltage change of deteriorated rechargeable battery 10 after breaking the charge or discharge current is more rapid than that of healthy rechargeable battery 10. The diagnostic means 8 can judge whether the rechargeable battery 10 is deteriorated or not based on such voltage change.

Abstract: Disclosed is a vibration test method for evaluating the vibration resistance of a specimen, comprising a test specification setting step (S10) of determining reference vibration conditions for the specimen based on transport conditions during actual transportation; a reference value attainment step (S20) of calculating an amplitude level and a reference accumulated fatigue value of the specimen under the reference vibration conditions; a test condition determination step (S30) of determining test vibration conditions and a test time based on an allowable amplification factor of the amplitude level and a desired vibration time, so that an accumulated fatigue value which is calculated from the vibration detection value of the specimen satisfies the reference accumulated fatigue value; and a vibration-imparting step (S40) of vibrating the specimen based on the test vibration conditions and the test time.

Abstract: A DRAM according to the invention is provided with a memory cell array formed by arranging in the row and column directions one-transistor-one-capacitor type memory cells; bit lines, precharged at a prescribed timing, for performing the transfers of write-in/read-out data to and from the memory cells; a sense amplifier including a first transistor, whose drains are connected to the bit lines to bias the substrate to a prescribed potential, and a second transistor whose drains and sources are connected to the sources of the first transistor and a ground potential point, respectively, whose gates receive an activation control signal and whose substrate is biased to the same potential as the first transistor is, for amplifying the signals of said bit lines when activated; an intermediate potential generating circuit for supplying an intermediate potential which is substantially equal to 1/2 of the source potential to the opposite electrodes of said memories and to the bit lines; a power turn-on sensing circuit f

Abstract: A power supply circuit for a DRAM has a power-on detection circuit which detects when an external power supply potential reaches a predetermined potential and produces first and second detection signals, and an internal power supply circuit which generates an internal power supply potential.