The utility model discloses a keep apart power core piece, include: emitting chip and receipt chip, and realize the transmission of power and the isolation of direct current common mode level throughhigh pressure resistant electric capacity C1, C2 between emitting chip and the receipt chip, emitting chip includes first oscillator, high pressure resistant electric capacity C1, C2, it includes therectifier circuit who comprises MOS pipe M1~M4, high pressure resistant electric capacity C5 to receive the chip, first oscillator power connection VDD1, first oscillator is connected with electric capacity C1, C2's negative pole respectively, and electric capacity C1, C2's positive pole is connected with rectifier circuit respectively, and rectifier circuit passes through electric capacity C5 power connection VDD2. This patent adopts high pressure resistant electric capacity to realize the transmission of power and the isolation of direct current common mode level, has improved the integratedlevel of chip. And the structure of the power core piece of this patent and implementation method both be fit for open -loop structure, is fit for loop configuration's system again. Under the condition that satisfies power isolation between two systems, the area and the consumption of having saved the chip again.