Light-controlled circuit characterization techniques are disclosed. For example, a technique for testing an integrated circuit includes the following steps/operations. At least a portion of the integrated circuit is stimulated with a light source so as to affect one or more electrical characteristics associated with the integrated circuit. By way of example, the light source may be a laser. Optical emissions are captured from the portion of the integrated circuit stimulated by the light source and/or one or more portions of the integrated circuit associated with the stimulated portion. The optical emissions are associated with one or more switching operations of one or more components of the integrated circuit. At least a portion of the captured optical emissions are processed to provide information about the integrated circuit.