Embodiments of the present invention relate generally to an electronic control unit for an airbag, said control unit having a data recorder unit that has a volatile memory, a nonvolatile memory and a copy circuit. The copy circuit is designed to copy data from the volatile memory to the nonvolatile memory during a second operating phase of the control unit. A protocol unit designed to record vehicle and/or accident data in the volatile memory is arranged in the data recorder unit during a first operating phase of the control unit. A first power supply unit is connected to the control unit and supplies the protocol unit and further components of the control unit with power and a second power supply unit is connected to the data recorder unit and supplies the latter with power.