EEPROM erase frequency

QWE4562009

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EEPROM erase frequency

How to understand the EEPROM erase frequency? How to choose EEPROM or flash based on the erase frequency? For example, the following case

Data is collected every 100ms, and 20 bytes are stored per second (the actual use of clearing the data stored in the EEPROM is to clear it three times a week. Is this also a kind of erase and write frequency?) In this application scenario, should we use an external EEPROM or the MCU's flash? Using flash can save costs! After all, the price of 128Kbit & SOT23-5 packaged EEPROM is a bit expensive! And we can't find domestic ones! Delivery time is also a problem. Currently, only Microchip in the United States has it!

lugl4313820

About 100,000 times, you can slowly calculate, it is not a very important place, you can cache it and then write it together.

吾妻思萌

Divide the theoretical lifespan by the frequency of your erases to see how long it can last.

wangerxian

Is there a parameter for erase frequency? Generally, it should be the number of erases.

qwqwqw2088

The question is about "EEPROM erase frequency" What do you want to ask?

Are you worried that the EEPROM erase and write frequency will affect the lifespan? In practice, the EEPROM data is cleared three times a week, which is a very low frequency.

The lifespan of flash is generally hundreds of thousands of times of erasure and rewriting, while that of eeprom is generally more than millions of times.

Don't think about life span at all.

qwqwqw2088

Or should I use an external EEPROM or the MCU's flash?
The storage units of the two are different.
The flash circuit structure is simpler. Compared with EEPROM, the same capacity occupies a smaller chip area, so the cost is naturally higher than EEPROM.

Also, is there no problem with the delivery date of American Microchip now?

Honghuzaitian

If you keep erasing and writing, it may become useless in a short time. This is not RAM that can be messed with all the time.

QWE4562009

How to understand the EEPROM erase frequency? Who can guide me on this?

QWE4562009

qwqwqw2088 posted on 2022-11-10 09:29 The topic is about "EEPROM erase frequency". I want to ask why you are worried that the EEPROM erase frequency will affect its lifespan? In actual use, clear the EEPROM storage...

I don't understand how the frequency of this erase is calculated.

QWE4562009

wangerxian posted on 2022-11-10 09:24 Is there such a parameter for erase frequency? Generally it should be the number of erases.

How to calculate the number of erases and writes here?

QWE4562009

Azuma Simeng published on 2022-11-10 06:35 Divide the theoretical lifespan by the frequency of your erasures to see how long it can last

For example, if the lifespan is 100,000 times, how many years can it be used?

QWE4562009

Data is collected every 100ms, 20 bytes are stored per second, and the EEPROM data is cleared three times a week. Which is the number of erase and write times? How many years can a lifespan of 100,000 times last?

wangerxian

QWE4562009 posted on 2022-11-14 16:10 How is the number of erases calculated here

[The actual usage of clearing the EEPROM stored data is three times a week], 13 times a month, 156 times a year. 100,000 times can be used for 641 years.

wangerxian

QWE4562009 Published on 2022-11-14 16:15 Collect data every 100ms, store 20 bytes per second and clear the EEPROM stored data three times a week, which one is the number of erase and write times? ? 100,000...

Filling up the file with all contents and then erasing it all counts as one time.

吾妻思萌

QWE4562009 Published on 2022-11-14 16:10 How is the number of erases and writes calculated here?

[The actual use of clearing the EEPROM stored data is three times a week], 13 times a month, 156 times a year. 100,000 times can be used for 641 years.

Flash is erased in blocks. Is it the bit line or the word line? I don't know. It can be erased 100,000 times, with a guaranteed 30% discount. If you calculate how many years it will take for 70,000 times, it will take at least 10 years.

freebsder

Refer to the device manual, they give conservative data.

damiaa

14400 times a day 288000 bytes

2,016,000 bytes per week

One week divided by three 672,000 bytes

Three times a week for 10 years is 1560 times.

The space required is very large. Check out the SPI flash plug-in.

A 2M byte W25Q16 costs about 2 yuan. If you want a CPU with 2M flash, it will be very expensive. Do you really think that CPU flash is cheap?

damiaa

QWE4562009 posted on 2022-11-14 16:08 How to understand the EEPROM erase and write frequency? Who can guide this work?

It's the number of erase and write times. If you use it too much, it's useless.

QWE4562009

wangerxian posted on 2022-11-14 16:25 Fill up all the content and then erase it all, which counts as one time.

So this is three times a week?

QWE4562009

damiaa posted on 2022-11-23 15:41 14400 times a day 288000 bytes a week 2,016,000 bytes a week divided by three 672,000 bytes ...

Data is collected every 100ms, 20 bytes are stored per second, and the EEPROM data is cleared three times a week. Which is the number of erase and write times? How many years can a lifespan of 100,000 times last?

Should it be counted as three times a week? After all, erasing once only counts as one.