Crystal oscillators are widely used in electronic devices to provide a precise and stable clock signal. However, not all crystal oscillators are created equal. In the automotive industry, automotive grade crystal oscillators (ACXOs) are used due to their higher reliability and stability compared to consumer-grade crystal oscillators. In this article, we will explore the differences between ACXOs and consumer-grade crystal oscillators, as well as their applications in the automotive industry. We will also provide examples of ACXOs used in various systems of Mercedes-Benz's EQ series, BMW's i-series, Tesla, Volvo's pure electric series, and NIO's ET series, along with their specific frequency and how the FCom brand produced by Fuji Crystal plays a role in this.

What is an Automotive Grade Crystal Oscillator (ACXO)?

An automotive grade crystal oscillator (ACXO) is a type of crystal oscillator that is specifically designed and manufactured for use in the automotive industry. It is built to withstand the harsh operating conditions of an automobile, such as temperature extremes, vibration, and electromagnetic interference. ACXOs are more expensive than consumer-grade crystal oscillators but offer higher reliability and stability, which are critical in automotive applications.

What is a Consumer-Grade Crystal Oscillator?

A consumer-grade crystal oscillator is a type of crystal oscillator that is commonly used in consumer electronics, such as smartphones, computers, and televisions. They are less expensive and less reliable than ACXOs, but they offer sufficient performance for most consumer applications.

Application of Automotive Grade Crystal Oscillator

ACXOs are used in a variety of automotive systems where accurate and stable timing is crucial. Some of the systems that rely on ACXOs include engine control units, transmission control units, airbag systems, infotainment systems, and advanced driver assistance systems (ADAS).

ACXOs in Mercedes-Benz's EQ Series

In Mercedes-Benz's EQ series, ACXOs are used in the vehicle's power electronics system. For example, the EQC uses a 20 MHz ACXO for the high-voltage DC-DC converter, which converts the high-voltage battery voltage to a lower voltage to power the vehicle's 12V electrical system. The EQS uses a 16 MHz ACXO for the control of the charging system, which provides precise timing for charging the vehicle's battery.

ACXOs in BMW's i-Series

In BMW's i-series, ACXOs are used in the vehicle's battery management system. For example, the i3 uses a 20 MHz ACXO for the battery management system, which monitors and controls the charging and discharging of the vehicle's battery. The i4 uses a 12 MHz ACXO for the power electronics system, which controls the vehicle's electric motor and regenerative braking system.

ACXOs in Tesla

In Tesla, ACXOs are used in various systems of the vehicle, including the battery management system, power electronics system, and infotainment system. For example, the Model 3 uses a 30 MHz ACXO for the vehicle's clock, which provides precise timing for the vehicle's various systems. The Model X uses a 20 MHz ACXO for the battery management system, which monitors and controls the charging and discharging of the vehicle's battery.

ACXOs in Volvo's Pure Electric Series

In Volvo's pure electric series, ACXOs are used in the vehicle's charging system. For example, the XC40 Recharge uses a 12 MHz ACXO for the on-board charger, which converts the AC power from a charging station to DC power to charge the vehicle's battery.

ACXOs in NIO's ET Series

The NIO ET7 also uses automotive grade crystal oscillators in various systems. For instance, the ET7's Advanced Driver Assistance System (ADAS) uses a 40MHz automotive grade crystal oscillator to ensure the accuracy of its sensing and computing systems. This helps the ET7's ADAS to detect and respond to potential hazards on the road more quickly and accurately, contributing to the overall safety of the vehicle.

In conclusion, the use of automotive-grade crystals, such as those used in the EQ series from Mercedes-Benz, i series from BMW, Model 3 from Tesla, pure electric series from Volvo, and ET series from NIO, play a critical role in the reliable and accurate operation of various systems in electric vehicles. With their superior frequency stability, temperature range, and environmental resistance, these crystals are essential components that help to ensure the safety and performance of next-generation electric cars. Companies like Fuji Crystal, with it’s FCom brand, are at the forefront of this technological innovation, driving the development of advanced, reliable, and efficient crystal oscillators that meet the demanding requirements of the automotive industry.