Operation of netX 51/52 at extended temperatures

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Last updated: 2016-10-07Version comment
Q

Is it possible to operate netX 51/52 at an ambient temperature Tambient of 105°C?

A

yes, in principle it is possible. The specified maximum junction temperature Tjunction of netX 51/52 is +125°C.

The netX 51/52 Technical Reference Guide lists the thermal package specification. With this data and the specification of the used heat sink, it is possible to calculate the maximum allowed ambient temperature to ensure Tjunction <= 125°C. This maximum Tambient might be >100°C, as long as Tjunction <=125°C.

However the expected lifetime is limited at high operation temperatures. Assuming 100% operation time at Tjunction = 125°C, the expected lifetime is 3 years. The following temperature profiles assure a expected lifetime of >= 10 years:

 

airflow [m/s]:0,5   
heat sink:yes, 6.5K/W   
Tambient [°C]TjunctionRatio1Ratio2Ratio3
105121,2 °C00,050,15
85101,2 °C0,050,10,25
5571,2 °C0,10,20,2
2541,2 °C0,10,250,15
521,2 °C0,150,20,1
-106,2 °C0,20,10,1
-25-8,8 °C0,250,050,05
-40-23,8 °C0,150,050
Lifetime(10yrs) OKOKOK

 

Furthermore the failure rate (FIT) rises at higher silicon temperatures. Please refer to chapter 4.5 Failure Rate (FIT) in the Technical Reference Guide of netX 51/52.

The Tambient of netx based products from Hilscher is specified to ensure a Tjunction <= 100°C in order to guarantee maximum reliability and lifetime. Therefore Hilscher recommends an operation at maximum Tambient of 85°C.

See also...