A semiconductor device includes a first high potential power supply, a second low potential power supply, a third power supply having a potential higher than the first, a fourth power supply having a potential more negative than the second, and an anti-fuse element having a node at each end, one of which is connected to the fourth power supply. A driver transistor has a source connected to the third power supply, a gate connected to a control node and a drain connected to one end of the anti-fuse element. A decoding circuit includes a load transistor connected between the third power supply and the control node and at least one selection transistor connected between the second power supply and the control node. A decision circuit is connected to the first and second power supplies. The decision circuit decides the resistance value of the anti-fuse element. The anti-fuse element is rendered electrically conductive in response to activation of the driver transistor as selected by the decoding circuit. The decision circuit decides whether or not the anti-fuse element has been rendered electrically conductive.