{{tag>collection_az vendor_sharp year_1992 year_1998 type_memory type_memory/flash type_memory/flash/nor foundry_sharp tech_250nm}}

BIOS flash chip from an Apple iBook Clamshell that tried to sneak into my dorm room sophomore year. Didn't survive ;)

Datasheet: "Flash Memory 8Mbit (512Kbitx16 / 1Mbitx8)" 

====== Package ======

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====== Die ======

Size is approximately 6410 x 5580 μm (35.76 mm<sup>2</sup>).

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Die revision markings and test structures

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Address grid markings on main flash array.

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Logic in upper left, focus on poly

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Same area, focus on M1

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Same area, focus on M2

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Looked like CMP filler over SRAM at first, but now seems to be NOR mask ROM given the non-repeating pattern.

16 bits per column x 16 columns = 256 bits. 3 μm vertical bit pitch, 386 μm high = 128 bits high. 32kbits = 4KB.

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