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The primary difference between EEPROM and FLASH is the removal of the ability to erase at the byte level. EEPROM和FLASH的主要区别是以字节为单位擦除内存的能力。 FLASH erases in much larger chunks of memory commonly referred to as sectors. Depending on the array size and the technology chosen, the sector size can vary significantly and therefore there is not a standard erase sector size across the industry and even within a product family. FLASH通常是按照扇区来擦除整块的数据。根据不同的工艺和技术的选择，扇区的大小差别很大，因此扇区的大小是没有标准的，每个厂家甚至每个系列产品的扇区大小都不见得一样。 The main point to remember is that the array is erased in large pieces as opposed to byte erase found in full featured EEPROM. 主要需要记住的是：EEPROM是按照字节擦除的，而FLASH是按照块擦除的。 Almost all commercially available FLASH memories utilized Fowler-Nordheim tunneling for the erase operation. 几乎所有的商业用FLASH都用一种叫（Fowler-Nordheim tunneling）的技术进行擦除操作。 The second major difference relates to programming and the programming size but here again there is not a clear standard across the industry. 第二个主要的区别在于编程，但同时和擦除相同的是，针对不同的厂家，编程的块大小也是不同的。 Some FLASH memories will do away with byte programming all together and will program in large sections referred to as pages. 一些FLASH内存废除了字节编程，只能按照块的大小进行编程写入。 Other FLASH memories still retain the ability to program in byte wide increments. The choice in programming width is mostly determined by the throughput of erasing the memory and completely reprogramming the array. 另一些FLASH内存还保留着字节编程的能力，这些能力取决于。。。（一些不重要的信息）。 There is also some diversity among FLASH memory products with respect to the programming method. 另外还有一些FLASH的差异，即写入的方式。 For example, some FLASH products use CHE and others use Fowler-Nordheim tunneling. As has been previously described in the EPROM and EEPROM overviews, each method has pros and cons, and it is these limitations that drive the programming size of the array. 例如，一些FLASH用CHE方式，另一些用（Fowler-Nordheim tunneling）方式。正如在EPROM和EEPROM中描述的，每种方法都有优缺点，这些优缺点限制了编程块的大小。 Remember from the discussion of EPROM that CHE requires a relatively high current, especially when compared to Fowler-Nordheim tunneling. 记住，EPROM中使用CHE需要高电流，尤其是和Fowler-Nordheim tunneling相比较的时候。 However, Fowler-Nordheim tunneling requires more time to program a memory location than does CHE. Therefore, to compensate for the longer time required per programming location using Fowler-Nordheim tunneling, the programming size is larger than that used with CHE. 然而，Fowler-Nordheim tunneling需要大量的时间写入内存。比较后可以得到，…（不重要） CHE cannot scale with respect to program size because of the high current required per bit to activate the mechanism. Although there are certainly power supplies that can supply many amps of current to a VPP pin on the part, there is an issue with power distribution within the |
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