In traditional power supply, even if two lines enter the power distribution box and double insurance is added, the power supply may be instantly pulled down to undervoltage due to the speed of insurance protection, resulting in power supply failure. Most of the autonomous driving Tier 1 requires the power supply branch to be quickly shut down for faults, and the isolation time is about 100µs, which is obviously impossible for fuses, and the protection action speed of semiconductors can be as fast as 10µs. The fault isolation can be realized by adopting the parallel design of dual power supply after isolation by MOSFET. For output single-circuit short-circuit fault, the isolation time can be shorter. In the new electrical and electronic architecture of Model 3, its power distribution architecture and load control all use semiconductor devices, and the power distribution architecture fully takes into account the power supply redundancy requirements for the safety of power supply and control functions of the current highly automated driving assistance system.