1. The Necessity of Low Voltage Operation in SoC Development Process

Recent advancements in semiconductor technology, with the evolution of fine process technologies such as 7nm, 5nm, and 3nm, have led to the miniaturization of transistors.

• Issues of Low Breakdown Voltage Due to Miniaturization: As miniaturization progresses, transistors require operation at lower voltages. Conventional voltages of 1.8V to 3.3V are no longer sufficient, and operation within the range of 0.9V to 1.5V is essential.
• Suppression of Leakage Current: It helps prevent unnecessary power consumption by operating at low voltages, which suppresses the increase in leakage current that accompanies miniaturization.
• Introduction of New Technologies: The adoption of new transistor technologies, such as FinFET and GAAFET, enables high-performance operation at lower voltages, achieving both high integration and low power consumption in SoCs.

2. Low Power Consumption as a Requirement for the Entire Vehicle

Low power consumption is required in the SoC for the entire vehicle due to the following reasons:

• Improvement of fuel and energy efficiency and compliance with environmental regulations: With the widespread adoption of electric vehicles (EVs), hybrid vehicles, and plug-in hybrid electric vehicles (PHEVs), the overall energy efficiency of the vehicle has become extremely important.  If the power consumed by the SoC is too high, it will increase battery consumption, leading to reduced driving range, worsened fuel efficiency, and making it more difficult to comply with environmental regulations such as CO₂ emissions standards and fuel efficiency regulations in various countries.
• Vehicle power supply limitations: Vehicle systems typically use a 12V battery for gasoline vehicles or a 48V battery for mild-hybrid vehicles, which must be converted to the extremely low voltage required by the SoC, ranging from 0.9 to 1.5V.Low voltage operation is preferable, as high operating voltages increase the load on the power supply circuit, leading to heat generation and reduced conversion efficiency.
• Thermal design and system reliability : Automotive SoCs must operate reliably even in high-temperature environments, such as those above 80°C. Reducing power consumption directly helps mitigate heat generation, easing the load on cooling solutions like air conditioning or auxiliary cooling fans, thereby contributing to enhanced overall system reliability.
• High-load processing for autonomous driving and ADAS: Autonomous driving systems and Advanced Driver-Assistance Systems (ADAS) require heavy processing for tasks such as cameras, LiDAR, and AI computation.
  As a result, more power is needed than before, making efficient low-power design essential. The adoption of low-voltage-driven processors dedicated to AI such as NPUs, DSPs, FPGAs, etc., enables power savings while maintaining processing performance.

Summary

Low power consumption and low voltage operation in automotive SoCs have two main aspects:

1. Challenges in the development process of SoC:
   • To address the reduced voltage tolerance due to miniaturization, a significant transition from the conventional 1.8V to 3.3V range to much lower voltages, ranging from 0.9V to 1.5V, is required.
   • Preventing an increase in leakage of current, which ensures longer lifespan and stable operation.
2. Requirements for the entire vehicle:
   • Power consumption reduction across the entire vehicle is required in response to the proliferation of electric vehicles and environmental regulations.
   • Efficient low-power design is essential to meet the constraints of vehicle power supply, thermal design, and high-load processing required for autonomous driving and ADAS systems.

Thus, low power consumption and low voltage operation in automotive SoCs represent essential technological innovations that cater to both the evolution of semiconductor technology and the increasing demands for higher functionality and precision in vehicle systems.