A rectifier comprising: n, wherein n is a natural number of 2 or larger, sets of series circuits in each of which a positive electrode side semiconductor device to be connected with a positive electrode side output terminal and a negative electrode side semiconductor device to be connected with a negative electrode side output terminal are connected in series with each other and a series-connection connection point is configured to be connectable with a corresponding AC power source, wherein each of the positive electrode side semiconductor device and the negative electrode side semiconductor device has at least a rectification function of making a current flow from a negative electrode side to a positive electrode side, wherein in each of the n sets, one of the positive electrode side semiconductor device and the negative electrode side semiconductor device is a MOSFET, wherein in at least one of the n sets, the other one of the positive electrode side semiconductor device and the negative electrode side semiconductor device is a specific diode, and wherein the specific diode is a Schottky barrier diode, wherein the MOSFET has a clamp circuit, wherein when the drain-source differential voltage obtained by subtracting the voltage of the source terminal of the MOSFET from the voltage of the drain terminal of the MOSFET becomes the same as or larger than a clamp voltage of the clamp circuit, the clamp circuit is configured to make a current flow from the drain terminal to the source terminal so that the drain-source differential voltage does not exceed the clamp voltage; characterized in that a breakdown voltage of the Schottky barrier diode is lower than the clamp voltage of the clamp circuit. n, wherein n is a natural number of 2 or larger, sets of series circuits in each of which a positive electrode side semiconductor device to be connected with a positive electrode side output terminal and a negative electrode side semiconductor device to be connected with a negative electrode side output terminal are connected in series with each other and a series-connection connection point is configured to be connectable with a corresponding AC power source, wherein each of the positive electrode side semiconductor device and the negative electrode side semiconductor device has at least a rectification function of making a current flow from a negative electrode side to a positive electrode side, wherein in each of the n sets, one of the positive electrode side semiconductor device and the negative electrode side semiconductor device is a MOSFET, wherein in at least one of the n sets, the other one of the positive electrode side semiconductor device and the negative electrode side semiconductor device is a specific diode, and wherein the specific diode is a Schottky barrier diode, wherein the MOSFET has a clamp circuit, wherein when the drain-source differential voltage obtained by subtracting the voltage of the source terminal of the MOSFET from the voltage of the drain terminal of the MOSFET becomes the same as or larger than a clamp voltage of the clamp circuit, the clamp circuit is configured to make a current flow from the drain terminal to the source terminal so that the drain-source differential voltage does not exceed the clamp voltage; characterized in that a breakdown voltage of the Schottky barrier diode is lower than the clamp voltage of the clamp circuit.