As autonomous driving technology continues to advance, the role and significance of Advanced Driver Assistance Systems (ADAS) are expanding. ADAS not only enhances the driving experience but also plays a critical role in improving driving safety by reducing traffic accidents. To further enhance the functionality and safety of ADAS, a range of advanced technologies and solutions are being introduced in this field. These innovative solutions encompass various areas such as sensor technology, data processing and analysis, artificial intelligence (AI), and network connectivity. The goal is to achieve more accurate environmental perception, streamline data processing, and provide reliable decision support for drivers. This article will delve into these diverse ADAS solutions while also exploring the related solutions offered by Murata to support these technological advancements.
Highly automated ADAS applications and architecture
ADAS provides real-time environment perception, driver assistance, and automated driving functions through various sensors and advanced data processing technologies. The main applications of ADAS include Automatic Emergency Braking (AEB), Lane Departure Warning (LDW) and Lane Keeping Assist (LKA), Adaptive Cruise Control (ACC), Blind Spot Monitoring (BSM), Traffic Sign Recognition (TSR), Parking Assistance (PA), among others, covering a wide range of automotive automation functions.
The architecture of ADAS consists of three main parts: the sensor layer, the data processing layer, and the decision execution layer. The sensor layer includes cameras, radar, LiDAR, and ultrasonic sensors. The data processing layer encompasses electronic control units (ECU) and high-performance processors, while the decision execution layer involves software algorithms and actuators.
The applications and architecture of ADAS aim to achieve more efficient driving assistance functions through advanced technologies, providing drivers with a safe and convenient driving experience and laying the foundation for future fully autonomous driving.
ADAS promotes rapid development of the semiconductor industry
ADAS applications encompass a variety of electronic components and semiconductor devices to support their sensing, data processing, and decision-making functions. Common semiconductor devices and electronic components in ADAS include image sensors, radar, LiDAR, ultrasonic sensors, as well as microcontrollers (MCUs), microprocessors (MPUs), graphics processing units (GPUs), application-specific integrated circuits (ASICs), and field-programmable gate arrays (FPGAs) for data processing. Communication devices such as in-vehicle network chips and wireless communication modules are also crucial, along with power management ICs (PMICs), voltage regulators, and memory devices like DRAM and flash memory. The development and innovation of these semiconductor technologies will further enhance and popularize ADAS functionalities.
Safety is an essential consideration in Advanced Driver Assistance Systems (ADAS) applications. Maintaining system reliability and security requires the integration of specialized electronic devices and technologies such as capacitors, EMI protection, and functional devices. Murata excels in these areas, and the following will introduce the related solutions that Murata can provide.
Meeting various needs of ADAS electronic control units
Murata is renowned for its comprehensive portfolio of electronic components tailored for Advanced Driver Assistance Systems (ADAS) applications. Specifically focusing on ADAS Electronic Control Units (ECUs), Murata provides a diverse selection of components including capacitors, EMI protection solutions, and sensors.
Murata's NFM series ceramic capacitors are 3-terminal low ESL (Equivalent Series Inductance) chip multilayer ceramic capacitors (EMI filters), suitable for automotive powertrains and safety equipment. These low ESL capacitors are particularly well-suited for power decoupling in power systems and safety control devices.
The NFM series ceramic capacitors from Murata feature low ESL, optimized for high-frequency characteristics. These capacitors are ideal for power decoupling in high-speed electronic equipment. Using low ESL capacitors allows maintaining the same function as 2-terminal capacitors while reducing the number of components. They effectively reduce noise and comply with AEC-Q200 standards.
Murata offers various products to advance in-vehicle networks. Notable products include common mode choke coils (CMCC), which are noise suppression components, and inductors for Power over Coax (PoC) technology, which combines signal lines and power lines into a single cable. CMCC utilizes characteristics that make it different for high frequencies signal and noise for high frequency noise suppression. PoC filters separate AC control signals from DC power supplied via the same cable, allowing only DC power to pass through.
In the area of EMI noise suppression filters (EMC noise countermeasures), Murata has introduced the DL/PL series of common mode choke coils/common mode noise filters. CMCC can be applied to differential transmission lines and is suitable for automotive applications such as CAN/CAN-FD/100Base-T1/1000Base-T1/SerDes/A²B™. It is also effective for common mode noise in power lines.
In addition, there are numerous EMI noise suppression filter products that can be applied to safety systems, CAN/FlexRay, CAN/CAN FD, in-vehicle Ethernet (100Mbps/1000Mbps), and SerDes (PoC). These products offer a wide variety of options.
Murata has also introduced several automotive PoC inductors, developed for PoC used in camera interfaces within ADAS. The LQW-F series inductors, along with other suitable inductors from Murata's extensive product lineup, enable wideband Bias-T circuits with minimal components. Murata's comprehensive range of automotive PoC inductors includes the LQW, LQH, LQM, and BLM series. These inductors for power lines come in a broad range of sizes from 1.6mm x 0.8mm to 12mm square, featuring different manufacturing processes such as metal alloy, ferrite multilayer, and wire-winding types.
Among them, the metal alloy inductors offer products in various sizes from 2.0mm x 1.6mm to 10mm square, supporting applications requiring high current and low loss. Using a metal alloy core, these inductors achieve high efficiency through unique manufacturing processes and the use of high-quality, highly reliable, and durable low-core-loss materials. All products meet the AEC-Q200 standards.
The SCA3300 accelerometer is a digital 3-axis accelerometer, featuring a significant performance improvement with dimensions of only 7.6 × 8.6 × 3.3mm (W × L × H). It offers selectable measurement ranges of 1.5g, 3.0g, and 6.0g. The sensor includes multiple self-diagnostic features, excellent zero-bias stability, low noise level, good vibration robustness, with an integrated SPI digital interface. It has superior mechanical damping characteristics, operates within a temperature range of -40 to 125°C, and consumes only 1mA of current (with a supply voltage of 3.0 to 3.6V). Utilizing Murata’s proven capacitive 3D-MEMS technology, it significantly improved performance in the industry.
Comprehensive product line to meet ADAS sensor application needs
In the realm of ADAS sensors, including cameras, radar, and LiDAR, Murata offers a comprehensive product line encompassing capacitors, EMI protection, and functional devices.
The automotive market is currently undergoing a significant transformation, with autonomous driving being one of the most notable trends. Consequently, the demand for LiDAR technology, which assists in autonomous driving, has surged in recent years. Murata’s silicon capacitors, with their low ESL characteristics, contribute to extending LiDAR detection ranges and improving measurement resolution.
Silicon capacitors, known for their small size and thin profile, can be placed near laser diodes. They can also be directly wire-bonded to the laser diodes, reducing the loop parasitic impedance between the capacitor and the laser diode. This feature enables the emission of high-output (over 100W) and short-duration (approximately 1.5 nanoseconds) light pulses, compared to ceramic capacitors.
Murata’s standard product line includes wire-bonding silicon capacitors such as the WBSC series, with an ESL of 50pH@SRF and a thickness of 250µm. The WLSC series offers an ESL of 50pH@SRF with a thickness of 100µm, and the WASC series provides an ESL of 6pH@SRF with thickness options of 100µm/250µm.
For EMI suppression in sensors, the previously mentioned automotive PoC inductors can be used, as well as metal alloy inductors, both of which offer excellent performance.
In terms of automotive timing devices (crystal resonators/ceramic resonators), Murata also has a rich product line applicable to ADAS (cameras), ADAS (radar), tire pressure monitoring systems (TPMS), remote keyless entry (RKE), Ethernet®, wireless chargers, NFC (keys), instrument clusters (general), instrument clusters (digital), parking assistance systems, surround-view camera systems, drive recorder, and electric/hybrid vehicles, among other applications.
Moreover, Murata also offers thermistors (temperature sensors) for temperature detection, preventing issues such as component damage, shortened lifespan, deformation, and burns. These sensors can monitor environmental temperatures, control fan speeds, or maintain working temperature ranges during fast charging. Thermistors are also used for overcurrent protection, suppressing abnormal currents to prevent short circuits due to assembly errors, accidental component damage, and miswiring in factory automation (PLC). Additionally, thermistors can be used for correcting the temperature characteristic curves of products like semiconductors, such as changes in semiconductor sensor output, physical changes in metal resistors, and rated changes in LEDs.
Thermistors are widely used in automotive applications, such as inverters in automotive electrification, BMS (Battery Management Systems), OBC (On-Board Chargers), DC-DC converters, engine ECUs, TCU (Telematics Control Units), IVI (In-Vehicle Infotainment), ADAS, APA (Automatic Parking Assistance), LiDAR, radar, and sensing cameras in automotive connectivity applications. They are also used in automotive body/chassis/safety applications, including automotive lighting, EPS (Electric Power Steering), PKE (Passive Keyless Entry)/TPMS (Tire Pressure Monitoring Systems), gateways, and in-vehicle LANs.
Murata’s thermistors include NTC thermistors and PTC thermistors (POSISTOR). NTC thermistors are devices where resistance decreases as temperature rises, while PTC thermistors are devices where resistance increases with rising temperature, enabling applications such as temperature detection and circuit current limiting.
Murata’s NTC thermistors use high-precision, high-sensitivity terminals and come in various models such as surface mount and lead types for inrush current suppression, temperature compensation, and more, available in sheet and lead type product series. POSISTOR PTC thermistors are made from ceramic materials with excellent reliability and performance.
Murata’s comprehensive thermistor product line covers different packaging formats (surface mount, leaded) and includes products for various applications such as overcurrent protection, overheat protection, and inrush current suppression.
Conclusion
As the automotive industry advances, prioritizing the enhancement of Advanced Driver Assistance Systems (ADAS) technology for improved functionality and safety is crucial. By incorporating cutting-edge sensor technology, robust data processing capabilities, and effective communication systems, ADAS systems are becoming more adept at accurately perceiving their environment and providing reliable decision support.
Furthermore, implementing redundant designs, utilizing high-reliability components, and integrating comprehensive safety measures are essential to ensure the stability and safety of ADAS systems across diverse driving conditions. The range of Murata solutions highlighted in this article is well-equipped to meet the demanding requirements for safety and performance in automotive ADAS applications.
For further details on the specific products mentioned or additional information, we recommend reaching out to Murata and Arrow Electronics for expert guidance and support.