A D/A converter performs a D/A conversion on digital light quantity indication data outputted from a CPU to generate an analog light quantity indication signal. The analog light quantity indication signal thus generated is supplied to both a power supply circuit and a light quantity control circuit comprising a photometric sensor, an integration circuit, and a comparison circuit. The light quantity control circuit outputs to a flash light emission circuit a light emission stop signal at the time point when the integrated quantity of light reaches a threshold according to the light quantity indication signal.
