HD6475348R Datasheet, PDF (331/487 Pages) Hitachi Semiconductor – Single-Chip Microcomputer

17.6 Erasing of Data
The windowed package enables data to be erased by illuminating the window with ultraviolet
light. Table 17-11 lists the erasing conditions.
Table 17-11 Erasing Conditions
Item
Ultraviolet wavelength
Minimum illumination
Value
253.7 nm
15 W·s/cm²
The conditions in table 17-11 can be satisfied by placing a 12000-µW/cm² ultraviolet lamp 2 or 3
centimeters directly above the chip and leaving it on for about 20 minutes.
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