AM28F256A-200JC

The Am28F256A is a 256 K Flash memory organizedas 32 Kbytes of 8 bits each. AMD's Flash memoriesoffer the most cost-effective and reliable read/writenon- volatile random access memory. The Am28F256Ais packaged in 32-pin PDIP, PLCC, and TSOP versions.It is designed to be reprogrammed and erased in-systemor in standard EPROM programmers. TheAm28F256A is erased when shipped from the factory.The standard Am28F256A offers access times as fastas 70 ns, allowing operation of high-speed microprocessorswithout wait states. To eliminate bus contention,the Am28F256A has separate chip enable (CE#)and output enable (OE#) controls.

AMD's Flash memories augment EPROM functionalitywith in-circuit electrical erasure and programming. TheAm28F256A uses a command register to manage thisfunctionality, while maintaining a standard JEDECFlash Standard 32-pin pinout. The command registerallows for 100% TTL level control inputs and fixedpower supply levels during erase and programming.AMD's Flash technology reliably stores memory contentseven after 100,000 erase and program cycles.The AMD cell is designed to optimize the erase and

programming mechanisms. In addition, the combinationof advanced tunnel oxide processing and low internalelectric fields for erase and programmingoperations produces reliable cycling. The Am28F256Auses a 12.0V±5% VPP high voltage input to performthe erase and programming functions.The highest degree of latch-up protection is achievedwith AMD's proprietary non-epi process. Latch-upprotectionis provided for stresses up to 100 milliamps onaddress and data pins from 1 V to V_CC +1 V.