I am building a DSP driven motor controller and I am looking for a way to implement fail on functionality. Currently the DSP controls a triac that turns on and off when needed. Unfortunately, it is driven by the on board power supply and in the event of a controller or power supply failure I would like the unit to continue to provide power to the load. So far the only solution I can come up with still requires the on board power supply to drive the triac when it is supposed to be on. This works if the error is in the DSP chip, but on a power supply failure it still turns off the load. Any ideas would be greatly appreciated.