A method for connecting an electronic component to a circuit board is disclosed. Initially, a substrate and an electronic component having solder located between them are placed under a flashlamp. Multiple light pulses from the flashlamp are applied to the electronic component, substrate and solder until the solder reflows. During the application of the light pulses, the power of one of the light pulses from the flashlamp and the temperature of the electronic component are measured, the measured power is converted to radiant exposure, and in response to the measured temperature of the electronic component, the duty cycle of a next light pulse is adjusted adaptively according to the radiant exposure of the one light pulse.