Abstract: A kind of high-accuracy and low-noise linear regulator power supply is designed for the requirement of certain receiver in airborne early warning radar. The structure of power supply system, the electro magnetic interference filter, the step-down transformer, the rectifier filter circuit, the power conversion circuit, the parallel redundant circuit and the protection circuit are theoretically analyzed and simulated. The work wave shape and test data of a test prototype are given. This power supply has functions of two-way parallel redundancy, output current limit protection and self-recovery, the output ripple can be less than 2 mV. This circuit design method has been widely used in airborne early warning radar receiver power supply domain.