262,144字×1位动态随机存取存贮器构成的系列,应用日立公司最新的2μm工艺制作。有2种型号的256K位DRAM。一种是常规的高速页面型DRAM。另一种具有一种新功能,即半字节型DRAM。半字节型DRAM可进行高速4位串行读/写操作。应用高存贮单元容量,金属折迭位线结构以及全Vcc存贮电路,可得到高α抗扰性。用冗余技术提高成品率。 262,144 words × 1 bit dynamic random access memory constitute a series of applications Hitachi latest 2μm process. There are 2 types of 256K bit DRAM. One is a conventional high-speed page type DRAM. The other has a new feature, nibbled DRAM. Nibble DRAM for high-speed 4-bit serial read / write operation. The use of high memory cell capacity, metal folding bit line structure and the entire Vcc memory circuit, high α immunity can be obtained. Use redundancy to improve yield.