Similarly, industrial motors operating in harsh environments, such as oil and gas drilling or automotive underhood environments, require components that can maintain efficiency and durability at elevated temperatures, which can reach up to 125 \({}^{\circ}\)C for electronics in automotive applications or even exceed 200 \({}^{\circ}\)C for oil and gas drilling, depending on the depth [13; 14]. The ability to operate at high temperatures not only enhances the reliability of these systems but also reduces the need for extensive cooling solutions, leading to more compact and efficient designs. Silicon carbide (SiC) and gallium nitride (GaN) technologies have emerged as pivotal advancements in the field of WBG semiconductors [15]. Recognized for their robustness against high radiation exposure and their ability to withstand extreme conditions such as high voltages and high temperatures, both SiC and GaN surpass traditional Si technology in these aspects [16; 17; 18]. Some of the features that can be pointed out are SiC devices enable operations at higher voltages, broader temperature ranges, and increased switching frequencies, while GaN devices offer greater electron mobility, reducing switching times and output capacitance. These technologies share some of these characteristics, and they are deeply analyzed and compared in the International Technology Roadmap for WBG Power Semiconductors [19], making SiC and GaN ideal candidates for applications in space-bound power systems and high-performance industrial environments. However, despite the advantages, these technologies also present challenges, such as higher manufacturing costs and more complexities in the material processing compared to Si, due to being a less mature technology [20]. In the field of power microelectronics, the maximum operational temperature for commercial ICs using Si-based devices is 250 \({}^{\circ}\)C. In contrast, several SiC-based transistor technologies have demonstrated functionality at temperatures as high as 600 \({}^{\circ}\)C [21]. A notable characteristic of SiC-based devices is their capability for high-temperature operation, although most commercial developments have focused on high-voltage discrete devices, particularly for power electronics and automotive applications. However, the operational temperature limit of SiC devices in power electronics is constrained by the liquidus temperature at the interface between the casing and the heat sink [22]. Consequently, CMOS technology for ICs incorporating SiC devices, as well as their performance under reduced or elevated atmospheric pressure, remains an active area of research. Recent studies on advanced wire bonding technologies for SiC indicate the potential to further enhance thermal operation [23]. Considering these factors, the contribution of this paper is to validate the design of an integrated DC-DC synchronous buck converter for use in extreme high-temperature environments, utilizing IISB's 2 \(\upmu\)m 4H-SiC CMOS technology, which is still under development and available via EUROPRACTICE [24]. By investigating the integrated converter performance under various parameters and varying temperatures, this study provides critical insights into the potential of this particular SiC technology for high-temperature applications. The article is organized as follows: Section 2 provides an overview of the DC-DC synchronous buck converter, including its design specifications and technology. Section 3 delves into the detailed circuit-level design, examining the components and their roles within the converter. The system implementation and simulation are discussed in Section 4, highlighting the performance and efficiency of the converter under various temperature conditions. Finally, the conclusions are summarized in Section 5.