Flyback boost circuit with current supplied to secondary side of transformer circuit prior to boost operation and strobe device using the same

A flyback boost circuit comprising:

• a transformer having a primary winding and a secondary winding, the secondary winding including
• an output terminal,
• an output voltage detection terminal configured to detect an output voltage, and
• a grounding terminal,
• a transistor connected to a primary side of the transformer and configured to generate a primary current by performing a switching operation,
• a control unit configured to control the switching operation of the transistor according to a result from comparing the output voltage to a reference voltage;
• wherein, prior to the start of a boost operation, the primary current is supplied to a secondary side of the transformer via the output voltage detection terminal to detect the output voltage, to thereby detect an unwired state by determining whether or not there is floating of the output voltage detection terminal or the grounding terminal.