Cut off power automatically in case the input voltage rises too high.

These devices are often designed to be very linear over a wide range of input voltages.

This effect can be used to amplify the input voltage or current.

In a full wave rectifier it is three times the input voltage.

This can be very significant if the input voltage is small, such as a low-voltage battery.

Thus the output affects the threshold and does not impact on the input voltage.

Thus the output "helps" the input voltage and does not affect the threshold.

In most cases, for positive input voltages, this means that the reference voltage will be negative.

The size of the number grows with an increase in the input voltage or current.

The input voltage of the Wilson current mirror is .