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Nor Flash

New Contributor

Hi,

I am using S25FL512SDSMFBG10 in my design, what is the maximum junction temperature I have to consider?

Also the Active Power Supply Current (WRR) (ICC3) specified in the datasheet is applicable to the maximum frequency  of operation?

If I am operating at a frequency below the maximum frequency, will the Active Power Supply Current (WRR) (ICC3) maximum will be less than 100mA?

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Moderator
Moderator

Hi,

The Theta Ja vale is 30°C/W and Psi Jt value is 0.25°C/W. You can use the following Application Note (http://www.cypress.com/file/210756/download ) to calculate the value of Tj. Please let me know if you have any further queries regrading this.

Regarding Active Power Supply Current query, if operating at a lower frequency the Active Power Supply Current should be lower than the maximum value. Could you please let me know which frequency you are operating on?

Thanks and Regards,

Apurva

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8 Replies
Moderator
Moderator

Hi,

The Theta Ja vale is 30°C/W and Psi Jt value is 0.25°C/W. You can use the following Application Note (http://www.cypress.com/file/210756/download ) to calculate the value of Tj. Please let me know if you have any further queries regrading this.

Regarding Active Power Supply Current query, if operating at a lower frequency the Active Power Supply Current should be lower than the maximum value. Could you please let me know which frequency you are operating on?

Thanks and Regards,

Apurva

View solution in original post

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New Contributor

Hi,

Thank you for support.

I Know that the junction temperature can be calculated using the formula. I want to know the maximum junction temperature supported by my device. I am doing worst case Analysis so I have keep a margin in junction temperature.

Using values in the datasheet for calculating junction temperature in the following formula

form.JPG

PH = ICC3*VCC = 100mA*3.6V = 360mW
Tj = 30.6°C/W * 360mW + 105°C = 116.016°C
Whether 116.016°C is the maximum junction temperature for S25FL512SDSMFBG10 device?


I am using 80MHz DDR. Whether ICC2, ICC3, ICC4, ICC5 will vary with the frequency I am using? How I can calculate the ICC2, ICC3, ICC4, ICC5 according to frequency of use?

current.JPG

This is the link of datasheet I am using http://www.cypress.com/file/177971/download

Thanks & Regards,
Alphonsa Yohannan

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Moderator
Moderator

Hi Alphonsa,

Regarding maximum junction temperature, I shall get back to you on this.

Regarding Active Power Supply Current, the values of ICC2, ICC3, ICC4 and ICC5 will always remain less than 100mA, regardless of the frequency.

Thanks and Regards,

Apurva

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New Contributor

Hi,

Thank you for your update.

Any information on maximum junction temperature?

Best Regards,
Alphonsa

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New Contributor

Hi,

Whether the junction temperature is above 125°C?

Best Regards,
Alphonsa

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Moderator
Moderator

Hi Alphonsa,

Could you please let me know your layer count and the size of the board?

Regards,

Apurva 

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New Contributor

Hi Apurva,


Layer count is 10.
Board size is 150mmx100mm.

Could you please let me know the dependency of size of board in maximum junction temperature?


Thanks & Regards,
Alphonsa

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Moderator
Moderator

Hi Alphonsa,

If program/erase are their worst case operations then we are okay with the above Tjmax calculation.

If however read is the worst operation then we need to know the application (total cap load) as well as frequency.

Could you please tell us how you are using our flash device?

e.g. What is the percentage of program/erase read operation performed in the application?

Regards,

Apurva

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