Is it safe to write data to MAX35103 flash memory

Question

I am using MAX35103 sensor in my project and I want to store some constant data into MAX35103 flash memory using STM32. However, I've read something that it is not safe to write data to the MAX35103 flash and this will shorten the life of the chip. Isn't it really safe to do this?

Answer 1

It depends what do you mean by safe.

All flash memories have a specification for how many times it can be erased and written until the memory cells are worn out and can't store data any more. So they degrade a little bit each write and erase cycle. The details of this are usually mentioned in the data sheet.

The write and erase also take time, and if for example user cuts off device power when MCU is storing new values into memory, the power cut may haopen middle of erase or write operation, so the memory contents may be left in any state and the data you were trying to store to flash is gone and it may contain no or partial data so the contents are corrupted.

So yes, writing to flash reduces the life time of the chip. Whether that is a problem, the life time depends on how often you write to flash and how many times the flash can be written.

And the system must be able to detect somehow if the flash contains valid data or has it been corrupted by power cut during a write or erase, so you know if the data is OK to use or not.

Answer 2

FLASH memories have limited guaranteed erase cycles number.

This IC FLASH has guaranteed 20k cycles. If you erase 10 times a day it will last 5.5years. You you need to erase more frequently you need to use EEPROM instead.