1 Scope
This part of GB/T 8446 gives the principles for measuring the thermal resistance and flow resistance of heat sink and specifies the testing system requirements, testing conditions and basic measurement procedures for air-cooling, self-cooling and water-cooling heat sinks.
This part is applicable to the testing of thermal resistance and flow resistance for the cast (including extruded) heat sinks, profile heat sinks and heat tube heat sinks for power semiconductor device.
2 Principles and Heating Current
2.1 Principles
The thermal resistance of heat sink is a measure of the heat sink's capability for dissipating the heat from the tube core of semiconductor device. Its value is defined as: in thermal balance, the ratio of the temperature difference between the specified point on the heat sink worktop and the specified point of cooling medium to the dissipation power for such temperature difference between the two points, see Formula (1).
Foreword i
1 Scope
2 Principles and Heating Current
2.1 Principles
2.2 Heating Current
3 Requirements and Instructions for Testing System
3.1 General Principles of Testing System
3.2 Testing System for Air-cooling Heat Sink
3.3 Testing System for Self-Cooling Heat Sink
3.4 Testing System for Water-Cooling Heat Sink
4 Test Conditions
4.1 Size of Heating Power
4.2 Installation Force for Heat Sink and Heating Device
4.3 Cooling Conditions of Heat Sink
4.4 Position for Measuring the Temperature of Reference Point
5 Measurements and Calculations
5.1 Preparations for Measurement
5.2 Regulating and Controlling Conditions
5.3 Measurement and Recording of Intermediate Parameters
5.4 Calculation of P and
