The power supply has a spec of the operating temperature range. If it operates under the condition outside the spec of the operating temperature range, the problem as shown in the following will be caused. Therefore, it is not allowed to be used under the condition outside the spec of the operating temperature range.

1. The case that the power supply is used at the temperature lower than spec

In this case, the power supply may not start up, or may repeat between output and no output. Even if the power supply can start up, the specifications will not be met, i.e. the output voltage may be unstable and the ripple and the ripple noise may be increased.

2. The case that the power supply is used at the temperature higher than spec

In this case, the temperature of the internal components will exceed their spec, and the power supply will become broken.