摘要:
A plurality of grooves 25 are formed in an outer peripheral surface of a cylindrical rubber magnet 17. The grooves 25 extend in a direction in which the cylindrical rubber magnet 17 is inserted into a yoke 3. The grooves 25 are open on both ends in the direction of insertion and are also open outwardly in a radial direction of the cylindrical rubber magnet 17. The grooves are formed at predetermined intervals in a peripheral direction of the cylindrical rubber magnet 17. When the cylindrical rubber magnet 17 is inserted into the yoke 3, an adhesive 15 gets into the grooves 25 without being pushed out of a lower end surface 21 of the cylindrical rubber magnet 17. The adhesive located between adjacent grooves also readily gets into the grooves 25. By presence of the adhesive got into the grooves 25, a necessary and sufficient amount of the adhesive can be uniformly interposed between a peripheral wall section 11 of the yoke 3 and the cylindrical rubber magnet 17.
摘要:
A semiconductor integrated circuit includes a bias voltage regulation circuit having variable resistors which are provided between voltage output circuits of higher and lower potential sides and changes corresponding to a specified condition such as V.sub.CC and a temperature. The variable resistors and bias voltage output circuits form a V.sub.CC divider, and the variable resistors properly regulate a bias voltage supplied to an oscillation circuit corresponding to each of the specified conditions. Accordingly, if the oscillation circuit is used in an automatic refresh circuit of a PSRAM, an increase of a refresh operation frequency is suppressed regardless of an increase in V.sub.CC. Since a temperature depending variable resistor causes a resistance value to be reduced by the predetermined characteristics against the temperature increase, it is possible to set an oscillation frequency to provide a desired pause for guarantee of circuit operation. It is possible to provide a ring oscillator having a low dependency of the oscillation frequency on a power source voltage and a temperature characteristic, thereby decreasing its current consumption.
摘要:
A polishing apparatus can stabilize polishing speed at the peripheral end portion of a polishing object, such as a wafer for fabricating a semiconductor device. The polishing apparatus performs polishing by arranging the polishing object in opposition to an abrasive cloth on a rotary polishing table, applying a load on a polishing block and with supplying a polishing fluid. A ring-shaped retainer is provided for embracing a given thickness of a elastic buffering plate provided between the polishing object fixing block and the polishing object for making contact pressure between the polishing object and the abrasive plate uniform and whereby for making a polishing speed of the polishing object constant.
摘要:
A semiconductor memory having dynamic memory cells includes a determining circuit for determining whether or not it is necessary to refresh the dynamic memory cells, and only when it is necessary, outputting a refresh execution signal in response to a refresh request signal from an external circuit, and a circuit for executing a refresh operation in response to the refresh execution signal. Even if the refresh request signal is supplied, a refresh operation is not executed unless the determining circuit determines that the refresh operation is necessary, thus dispensing with unnecessary refresh operations. Preferably, the determining circuit includes a timer which outputs a signal at every predetermined period. Only when the signal is output from the timer, is the refresh request signal from an external circuit accepted and the refresh execution signal output.
摘要:
A first groove for an upper interconnection and a second groove for a bonding pad are formed on a silicon dioxide film including a lower interconnection, and a through-hole is formed to connect the first groove to the lower interconnection. At the same time with the formation of the through-hole, the second groove is deepened by the common etching process. Then, an Al film is formed on the silicon dioxide film, and the Al film is polished to be removed except for the Al film in the first and second grooves to provide the upper interconnection and the bonding pad.
摘要:
A refresh control circuit for a pseudo static random access memory includes a refresh control signal output circuit for outputting a refresh control signal to accomplish refresh control of the pseudo static random access memory, and includes a delay circuit. A first chip enable signal from a control device such as a MPU is delayed by the delay circuit and outputted as a second chip enable signal for the PSRAM. As the first chip enable signal level changes from a selection level to a non-selection level, the refresh control signal level also changes to a non-refresh level. This state is maintained for a predetermined period. After the second chip enable signal changes from the selection level to the non-selection level, the refresh control signal returns from the non-refresh level to the refresh level. Thus, the PSRAM enters into the refresh state during the non-selection state, and is refreshed. This refresh operation is necessarily performed after an access to PSRAM.
摘要:
Disclosed is an air conditioner for attempting to improve on the corrosion of the outdoor unit. The air conditioner of the present invention for performing a cooling operation and a heating operation by switching a four side valve, that includes an outdoor side heat exchanger operating as a condenser during the cooling operation and an evaporator during the heating operation, and having fins and heat transfer tubes, wherein the outdoor side heat exchanger is placed on a baseboard which configures a lower portion of a chassis of the outdoor unit, comprises the fins and the heat transfer tubes of the outdoor side heat exchanger that are constructed with aluminum or aluminum alloy, and the baseboard that is constructed with Zn—Al plated steel board or Zn—Al—Mg plated steel board.
摘要:
A refresh control circuit for a pseudo static random access memory includes a refresh control signal output circuit for outputting a refresh control signal to accomplish refresh control of the pseudo static random access memory, and includes a delay circuit. A first chip enable signal from a control device such as a MPU is delayed by the delay circuit and outputted as a second chip enable signal for the PSRAM. As the first chip enable signal level changes from a selection level to a non-selection level, the refresh control signal level changes to a non-refresh level. This state is maintained for a predetermined period. After the second chip enable signal changes from the selection level to the non-selection level, the refresh control signal returns from the non-refresh level to the refresh level. Thus, the PSRAM enters into the refresh state during the non-selection state, and is refreshed. This refresh operation is necessarily performed after an access to PSRAM.
摘要:
A virtual type static semiconductor memory device according to the present invention comprises a refresh detector circuit for detecting the enabling operation of a refresh control circuit and a terminal for outputting to an outside a detection signal which is generated from the refresh detector circuit. The virtual type static semiconductor memory device informs a present refresh operation to the outside when it is accessed from the outside during the time period in which a refresh operation is conducted in the semiconductor memory device. A system employing the semiconductor memory device allows a slow access at that time only and allows access to be gained to the semiconductor memory device at high speed at other times.