Page 193 - Bebop to The Boolean Boogie An Unconventional Guide to Electronics Fundamentals, Components, and Processes

174 ChapterFifieen

small quartz window mounted in the top. The quartz window is usually covered
by a piece of opaque tape. To erase the device, the tape is removed and the
EPROM is exposed to ultraviolet radiation for approximately 20 minutes.
EPROMs are relatively expensive due to their complicated packaging require-
ments, but are ideal for prototyping and other applications that require regular
changes to the stored data. EPROMs are often used during the development
of a design and are subsequently replaced by equivalent PROM or ROM
devices in cheaper plastic packages after the design has stabilized. (The actual
construction of EPROMs and some of the other types of memory devices
introduced during the remainder of this chapter are discussed in greater detail
in Chapter 16.)

18 In conversation, EPROM is pronounced as ”E-PROM.” That is, spelling out the “E and
following it with “prom.”