Failure through electrical stress
SAQ
Components can fail from the application of excessive forward voltage,
creating a current overload, from the application of a reverse voltage,
and from subjecting them to short duration, high voltage transients.
The latter cause failure because the thermal inertia of the device
is such that power is not dissipated sufficiently quickly.
The most vulnerable types of device are:
- Electrolytic capacitors, which will fail under comparatively
low reverse voltages
- Silicon power devices, where variations in thermal resistance
can lead to destructive hot spots under current overload
- For transient voltages, small semiconductor devices, or those
with connections outside the assembly, especially interface devices
which may terminate a long cable in an uncontrolled electrical
environment.