8542.32.00.61 - Erasable (except electrically) programmable read-only memory (EPROM)

This classification covers erasable programmable read-only memory (EPROM) integrated circuits. EPROMs are a type of non-volatile memory that can be written to and erased using ultraviolet light. Once erased, they can be reprogrammed with new data. This contrasts with ROMs that are programmed during manufacturing and cannot be changed, and with RAM which is volatile and loses its data when power is removed.

Within the broader category of "Memories," this specific sub-heading distinguishes EPROMs from other types of integrated circuit memory. It is differentiated from electrically erasable programmable read-only memory (EEPROM) (8542.32.00.51) by the method of erasure; EPROMs require physical exposure to UV light, whereas EEPROMs are erased using electrical signals. It is also distinct from dynamic random access memory (DRAM) and static random access memory (SRAM), which are volatile read-write memories.

As a leaf node within the HTS classification system, 8542.32.00.61 does not have further subdivisions. Therefore, classification under this code is definitive for EPROM integrated circuits that do not meet the criteria for electrically erasable programmable read-only memory or other memory types. This would include devices where data storage is achieved through the presence or absence of electrical charge in floating gate transistors, and where erasure is facilitated by the application of ultraviolet radiation through a transparent quartz window.