Low temperature test of electronic products: how long do components usually fail at low temperature?

Date：2021-07-26 13:46:00 Views：5348

Introduction to low temperature test:

GB / T 2423.1-2008 / iec60068-2-1:2007 environmental testing of electric and electronic products Part 2: Test methods test a: low temperature test

The low temperature test involved in this standard is applicable to non heat dissipation and heat dissipation test samples This standard is only used to assess and determine the environmental adaptability of electrical and electronic products (including components, equipment and other products) stored and used under low temperature environmental conditions.

How long do components usually fail at low temperature?Most electronic components have a service temperature range, beyond which they will fail or their performance will be reduced. Generally, the civil grade is 0 ~ 70 ℃, the industrial grade is: - 40 ~ 85 ℃, and the military grade is: - 55 ~ 128 ℃. This is because it refers to the material whose conductivity is between conductor and insulator at room temperature. The change of temperature has a great impact on the conductivity, limit voltage, limit current and switching characteristics of semiconductor. Now a chip often contains millions or even tens of millions of transistors and other components. The accumulation of each small deviation may have a great impact on the external characteristics of semiconductors. If the temperature is too low, the chip will often fail to open its internal semiconductor switch under the rated working voltage, resulting in its failure to work normally.

The low temperature test cannot be used to assess the resistance of the test sample to temperature change and its working ability during temperature change. In this case, the temperature change test method shall be selected

Low temperature test of non heat dissipation test samples: temperature mutation test and temperature gradient test;

Low temperature test of heat dissipation test sample: a type of temperature gradient test

This test method is usually used for test samples that can achieve temperature stability during condition test The test duration is calculated from the time when the temperature of the test sample reaches stability Under special circumstances, if the temperature stability of the test sample cannot be reached during the condition test, the test duration shall be calculated from the time when the test chamber reaches the specified test temperature.

Low temperature test conditions:

Selection of low temperature test severity level for sudden change or gradual change of temperature of non heat dissipation test samples:

65℃、55℃、40℃、25℃、10℃、-5℃、5℃

The temperature range can have a positive and negative deviation of 3 degrees, and the test duration is generally 2h, 16h, 72h and 96h Or select the test time according to the product's own use environment. If the purpose of the test is only to check whether the test sample works normally at low temperature, the test time is limited to stabilizing the sample temperature.

Low temperature test humidity range:

Electronic products are generally high temperature, high humidity and alternating temperature. Low temperature is generally - 10 ℃ and high temperature is 60 ℃ and 80 ℃. The humidity is generally 80.

Low temperature test equipment:

Low temperature test chamber can be used to assess and determine the adaptability of electrical, electronic, automotive electrical appliances, materials and other products to storage and use under high and low temperature environmental conditions. It is suitable for schools, factories, military industry, research institutes, etc.

Meet the standardLow temperature test equipment meets GB / t2423: 1-2001 GB/T2423. 2-2001 and other national standards.

Low temperature test standard the conventional test standard is as follows:

Environmental testing of electric and electronic products Part 2: Test methods test a: low temperature GB / T 2423.1-2008 / IEC 60068-2-1:2007

Packaging - Basic tests for transport packages - Part 2: temperature and humidity conditioning treatment (GB / T 4857.2-2005 / ISO 2233:2000)

Basic technical conditions for automotive electrical equipment QC / T 413-2002

Military equipment laboratory environmental test methods Part 4: low temperature test GJB 150.4a-2009

General specification for military communication equipment GJB 367a － 2001

General specification for military electronic test equipment gjb3947a-2009

Environmental test of ship electronic equipment low temperature test GJB 4.3-1983

Environmental test of ship electronic equipment low temperature storage test GJB 4.4-1983

Rail transit rolling stock electronic devices GB / T 25119-2010 / IEC 60571:2006

General specification for electronic measuring instruments GB / T 6587-2012

High temperature and low temperature test methods for railway ground signal products TB / T 2953-1999