For D-Flash in MC9S12XET256, what is the number of program/erase cycles? As per appendix, should we consider the the min value(50K) or typical value(500k^3)

[subashr]

I'm working on emulated eeprom for MC9S12XET256.

I referred the appendix in the manual, for the maximum number of program/erase cycles of DFlash. It has 2 values min(50K) and typical(500K^3).

Which value can be considered for implementation - Min / Typ?

[RadekS]

Hi Subash,

It depends on conditions of use – mainly temperature.

The min(50K) value refers to whole temperature range. The typical(500K) value is valid with condition that TJavg does not exceed 85°C in a typical temperature profile over the lifetime of a consumer, industrial or automotive application.

The typical endurance is defined as the number of P/E cycles that most parts can achieve without failure. It is evaluated by stressing an industry standard sample size (Typically, 3 lots, 77 units per lot) at room temperature (TJavg < 85°C for S12XE) until intrinsic wear out is observed or until extensive margin to the endurance specification has been achieved.

Some more details may be found at:

http://www.nxp.com/assets/documents/data/en/engineering-bulletins/EB618.pdf

http://www.nxp.com/assets/documents/data/en/engineering-bulletins/EB619.pdf

So, if MCU Tjavg in your application will be close to the maximum value of appropriate temperature range, please calculate rather with a minimum number of program/erase cycles.

I hope it helps you.

Have a great day,
Radek

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[subashr]

Hi Radek,

Thanks for your reply. It's helpful.

The typical value as per manual is 500K to the power 3 (500K^3). ie., 500,000,000,000. Hope I'm correct.

Subash.

[RadekS]

Hi Subash,

Unfortunately, no. The typical value as per manual is 500K = 500,000. The number 3 just references to note 3 below this table (“TJavg does not exceed 85°C in a typical temperature profile over the lifetime of a consumer, industrial or automotive application.”).

I am sorry for confusing.

I hope it helps you.

Have a great day,
Radek

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Note: If this post answers your question, please click the Correct Answer button. Thank you!
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[subashr]

Hi Radek,

Thanks for your clarification. 

Have a great day,

Subash