In this paper, a novel double RESURF LDMOS with multiple rings in non-uniform drift region is proposed and successfully fabricated. The proposed device maximizes the benefits of the double RESURF technique by optimizes key process and device geometrical parameters in order to achieve the lowest on-resistance with the desired breakdown voltage. In addition, a versatile JFET device is firstly developed. The JFET device cannot only be used as the current detector, but also be used as the internal power supply for SPIC. Besides, it is compatible with Bipolar-CMOS technology, without any additional processes required.