Specifications
11
Dec. 20
Mitsubishi IPM-series Application Note
Reliability
7-2-2. Power Module Failure Reason
After a piece of equipment has been assembled and adjusted, or has been placed in field service, failed devices that are returned
to the factory are analyzed to determine the cause of failure. This procedure is intended to determine whether the problem lays
with the device itself, or the manner in which it was used. This section will list potential reasons of failure.
Good ֣֣֣֣֣֣֣֣֣֣֣ Device Unmatch for Circuit or Usage Condition
Usage Condition֣֣
֣
֣
֣ Over voltage
ֿ֥֣ V
CE
Over voltage (Collector-Emitter)
ֿ֥֥ Switching Surge
ֿ֥֥ Bus Bar Voltage Rise
ֿ֥֥ Abnormal Control Signal
ֿ֥֥ Interfered Noise (Lightning Surge)
ַ֥֥ Inappropriate Measurement
ַ֥֣ V
GE
Over voltage (Gate-Emitter)
ֿ֥ Static Electricity
ֿ֥ Abnormal Gate Drive Circuit
ֿ֥ Gate Oscillation
ֿ֥ High Voltage Applied
ַ֥ Interfered Surge
ֿ֣֣ Over Temperature (Over Current, Over Load)
ֿ֥֣ Inappropriate Thermal Design
ֿ֥֣ Short Arms (Not Enough Dead-Time, False Turn-on )
ֿ֥֣ Over Current
ֿ֥֣ Under Gate Drive Voltage
ֿ֥֣ Gate Circuit Open
ֿ֥֣ Abnormal Switching Frequency Increase
ֿ֥֣ Abnormal Switching Frequency Decrease
ֿ֥֣ Inappropriate Thermal System
ַ֥֣ Bonding Surface Fatigue
ַ֣֣ Insulation Failure (Ceramic Crack, Internal Solder Melting)
ֿ֣ Heat Sink Mounting Failure (Over Stress)
ַ֣ Over Voltage
Power Device Defect
֣
֣
֣ IGBT Chip Manufacture Defect
ֿ֥֣ Pattern Defect
ַ֥֣ Surface Fault (Impurity ion)
ַ֣ Module Manufacture Defect
ֿ֣ Wire Bonding Fault
ֿ֣ Connection Fault Between Insulation Base Plate and Module Base Plate (Solder, etc.)
ֿ֣ Internal Electrode Solder Fault
ַ֣ Metalization Fault
Operation life is dependent on the internal wire bonding, thermal fatigue between insulation base-plate and module base-plate.
The thermal fatigue will be described in the next page.