The AT27BV1024-90JU is a non-volatile Electrically Programmable Read-Only Memory (EPROM) device manufactured by Microchip. It features 64K x 16 bits of memory, operating from a single 2.7V to 3.6V power supply, with a 90ns access time. The device is housed in a PLCC44 package. It provides the benefits of EEPROM technology, but without the need for battery back-up and write cycles are performed without the need for external control. As an Erasable Programmable Read-Only Memory (OTP EPROM), the device is programmed and erased with an ultraviolet light source.