Provided is a secondary-side module which can improve reliability. A secondary-side module (400) comprises: a synchronous rectification controller (300) that controls a synchronous rectification transistor (M2); and a shunt regulator (206) that generates a current that corresponds to the difference between an output voltage VOUT of a DC/DC converter (200) and the target value of the output voltage, which are housed in a single package. The multiple pins to be connected to the shunt regulator (206) are all laid out along a first side (E1) of the package.