Capacitive discharge SCB initiation of energetic materials was discussed at different firing voltage levels. Both of SCB are the same resistance and difference mass. The energetic materials are LTNR and PbN₆. For the SCB device, there are three modes of igniting energetic materials, electrothermal ignition, electrical explosive ignition and plasma ignition, respectively. To understand further the behavior of SCB ignition, we measured the critical ignition voltage and ignition time of SCB/LTNR and SCB/PbN₆ device. As a result the critical ignition energy is not only related with energetic materials, but also the comparable mass of the SCB bridge, so there is an optimal design mass about SCB bridge. Besides, the LTNR was more sensitive than PbN₆, however, the burning rate of PbN₆ is higher than that of LTNR.