The modern CPU technology scaling with increasing transistor density causes an exponential growth of both dynamic and static power dissipations that affecting the microprocessor’s performance. The body bias voltage (VBB) and supply voltage (VDD) extent to decrease to maintain the low power requirements. Joint body biasing and voltage scaling is an efficient technique that reduces the power dissipation of CPUs and high performance digital devices when peak performance is unneeded. Switching networks have become an essential component in the design of digital ICs that require the ability to control and select a specified threshold voltage/body-bias and supply voltages (VTH/VBB-VDD) for the microprocessor chip. This paper presents a complete design of a switching network for joint body biasing and supply voltage scaling (VBB-VDD), which is consistent in allowing compact low power consumption and low temperatures in the core of high-performance processors. The results show the roles and effectiveness of the switching network that adaptively selects the VTH/VBB-VDD sets for different workloads and simulation environments and all temperature ranges.