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This article shows you how to choose nonvolatile SRAM, concise and easy to understand, absolutely can make your eyes shine, through the detailed introduction of this article I hope you can gain something.

With the rapid development of semiconductor technology, a variety of memories have been introduced, and their performance has been continuously improved. At present, there are mainly the following types of memory: static RAM(SRAM), dynamic RAM(DRAM)EPROM,EEPROM, FLASH MEMORY. A new type of memory, nonvolatile SRAM(NVSRAM), which is composed of SRAM, backup battery and corresponding control circuit, is discussed.

In order to solve the problem of SRAM data preservation, foreign famous semiconductor companies took the lead in introducing NV-SRAM series products that can completely replace SRAM, and similar products have also been produced in China. In the face of many NVSRAM products, how do users choose high quality and low price products? It is recommended that users choose according to the following performance indicators and prices:

Reliability of protection data: refers to whether NVSRAM is miswritten during power failure on the system, which is the most important performance indicator of NVSRAM, and it is also the most concerned by users and difficult to test at the time of purchase. Although manufacturers claim that their products are foolproof data protection, in fact, very few really do this. Most NVSRAM products lose data when used, causing a lot of problems and inconvenience to users. This is mainly due to the following reasons: power-on without protection delay, loss of data during power-on; power-off when the main power supply voltage drops quickly, protection circuit can not quickly switch the power supply of SRAM from the main power supply to the backup battery, or the SRAM chip selection signal blocking is not timely.

Second, protection voltage: protection voltage is mainly set to prevent the upper. Miswriting of data during power failure. For the user, the lower the protection voltage, the better, in the case of completely reliable protection data.

Third, power-on protection delay: This refers to how long the NV-SRAM delay can be accessed when VCC is higher than the protection voltage when the system is powered on. This delay is necessary because the system may not work properly when VCC is higher than the protection voltage, and it may be in a reset state or an uncertain state, which is very likely to misstate NVSRAM. NVSRAM internal circuit with necessary protection delay can effectively prevent miswriting during power-up. Users should pay attention to the delay parameters of the product when using NVSRAM. It is best to test whether NVSRAM can be accessed before the system works; or add a delay program in the initialization program.

4, the use of temperature range: some NVSRAM product protection voltage will change with temperature changes. If the NV-SRAM system requires a large temperature range, you can use the following methods to do a simple test: put NVSRAM in the refrigerator freezer for about half an hour, and then immediately plug in the system to test whether the system can read and write NV-SRAM normally.

5. Access speed: All kinds of NV-SRAM products are marked with access speed, and users can choose according to the requirements of their own application system.

Six, power consumption and service life: foreign products use low power chips, internal control circuit in the normal operation of the system current less than 1mA, the system power down when switching to battery power supply, at this time the current is only about 100nA. NV-SRAM uses lithium battery as backup power supply, because lithium battery self-consumption is extremely low, NVSRAM service life can generally be about ten years.

7, price: In general, foreign products are expensive, domestic products are cheap, but for the chip to lose data, even if the price is cheaper, it is recommended that users do not choose.

That's how to choose nonvolatile SRAM. Have you learned anything or skills? If you want to learn more skills or enrich your knowledge reserves, please pay attention to the industry information channel.

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