The W27E520 is a 64k×8 bit electrically erasable EPROM device with high speed and low power consumption. It has internal latches for the lower 8 address lines to multiplex with the 8 data lines, which can save external TTL components, reduce cost and space. In normal read mode, it only needs one power supply within the range of 4.5V to 5.5V. The W27E520 also provides an electrical chip erase function, which is very convenient for changing/updating the contents in the device.