Automotive MEMS Inertial Measurement Units Comparison 2024
According to MEMS Consulting, the Inertial Measurement Unit (IMU) is a device that measures the attitude angle (or angular rate) and acceleration of an object. Typically, the IMU integrates a three-axis gyroscope and a three-axis accelerometer, as well as motion/attitude algorithms. For increased reliability, redundant sensors can also be equipped for each axis. If the sensors integrated in the IMU are implemented using MEMS technology, then they can be called MEMS IMUs, and their main applications are smartphones, AR/VR devices, automobiles, robots, etc. In the automotive sector, in-car navigation systems are becoming the standard for autonomous vehicles, and shipments of automotive-grade 6-axis MEMS IMUs are increasing day by day, with Murata and Bosch leading the field, TDK InvenSense actively participating in them, and many Chinese MEMS manufacturers investing in R&D and developing alternative products.
This report provides detailed physical analysis of the mainstream automotive-grade MEMS IMUs (Bosch SMI240, Murata SCHA634, and TDK InvenSense IAM-20685) from three of the world's leading MEMS vendors, including device disassembly, chip profiling, and material analysis, and inferences about the MEMS chip manufacturing process and packaging process, as well as comparative analysis at the device and chip level. Finally, the report also retrieves and analyzes the patent status of these three MEMS IMUs, providing a mapping from patent to product.
The SMI240 is a six-axis MEMS IMU product launched by Bosch for automotive advanced driver assistance systems (ADAS), enabling high-precision integrated navigation applications. Housed in a small LGA-16 pin package, the SMI240 features an integrated 3-axis gyroscope and 3-axis accelerometer, an operating temperature range of -40 to 105°C, and ASIL B functional safety qualification and AEC-Q100 Grade 2 reliability standard qualification, providing the system with high accuracy and reliability of inertial sensing data. Among them, the gyroscope range is ±300°/s, the noise is controlled at ±0.1°/s (@50Hz), the accelerometer range is ±16g, and the noise is as low as ±4mg(@50Hz).
Bosch MEMS IMU:SMI240
The SCHA634 is a Murata automotive-grade six-axis MEMS IMU that can realize advanced driver assistance systems (ADAS) and autonomous driving (AD) functions by fusing data with various sensors such as GNSS (Global Navigation Satellite System), cameras, millimeter-wave radar (RADAR), and LiDAR (LiDAR). The product offers advantages in bias stability and noise to meet the performance needs of automotive safety applications. Murata also calibrates the orthogonality of the sensor's measurement axis, allowing system integrators to skip this costly and operationally demanding process.
The Devil's Eye: SCHA634
The IAM-20685 is an ISO 26262 ASIL B compliant automotive-grade six-axis MEMS IMU that leverages TDK InvenSense's proprietary CMOS-MEMS technology to integrate a 3-axis accelerometer and 3-axis gyroscope on a single chip, providing a very small but high-performance low-cost package with an on-chip 16-bit ADC, programmable digital filter, embedded temperature sensor, and high robustness by supporting 10,000g impact reliability. Applications include automotive advanced driver assistance systems (ADAS), autonomous driving (AD), inertial navigation, dead reckoning, and more.
TDK InvenSense MEMS IMU：IAM-20685
The report "Comparative Analysis of Automotive-grade MEMS Inertial Measurement Unit (IMU) Products-2024 Edition" mainly includes the following three aspects:
1. First, the SMI240, SCHA634, and IAM-20685 packages were photographed and analyzed, and the device packages were 16-pin LGA, 32-pin SOIC, and 24-pin DQFN, respectively. Then the device is mechanically opened and chemically deglued, and the chips are taken out: the first two are MEMS chips and ASIC chips 3D stacked, and the latter is CMOS-MEMS integrated chips, and then the chips are analyzed by structure and materials, including ASIC circuit layer, MEMS structure layer, MEMS cap layer, wafer-level bonding, etc., and local close-ups and feature sizes of MEMS accelerometer and MEMS gyroscope triaxial sensing structure and drive structure are provided respectively.
Bosch MEMS IMU SMI240整体视图(X-Ray扫描)
Murata MEMS IMU SCHA634的陀螺仪芯片分析示例
TDK InvenSense MEMS IMU IAM-20685剖面分析示例
2. Compare the above three automotive-grade MEMS IMUs in all aspects, including device performance, packaging, integration, ASIC, and MEMS chips. All three are six-axis IMUs, but there are differences in the chips integrated inside. The SMI240 has 3 chips: 1 3-axis accelerometer, 1 3-axis gyroscope, and 1 ASIC, SCHA634 has 6 chips: 1 3-axis accelerometer, 3 single-axis gyroscope, and 2 ASICs, and the IAM-20685 has only 1 six-axis CMOS-MEMS integrated chip. In addition, these three products have the same sensing method: accelerometer X/Y in-plane motion sensing, Z-direction out-of-plane motion sensing, gyroscope X/Y out-of-plane motion sensing, Z-in-plane motion sensing.
Comparison example of three automotive-grade MEMS IMU chips
3. Conduct relevant patent search and analysis for the dismantling and analysis of the above three automotive-grade MEMS IMU products, and provide a mapping relationship from patent to product, which is helpful for other manufacturers to understand the technical points and the scope of patent protection, and conduct infringement correlation analysis, so as to effectively avoid the occurrence of infringement disputes.
Bosch MEMS IMU SMI240专利到产品的映射关系示例
Table of Contents:
1. Summary of the report
- Summary of the report
- Analyze processes and methods
2. Company Introduction
- 罗伯特·博世（Robert Bosch）
* Company Introduction
* IMU MEMS(SMI240)介绍
- 村田（Murata）
* Company Introduction
* MEMS IMU(SCHA634)介绍
- TDK应美盛（TDK InvenSense）
* Company Introduction
* MEMS IMU(IAM-20685)介绍
3. Physical analysis
- Physical analysis methods
- How the device works
- Bosch IMU:SMI240
* Overview of physical analysis
* Device package view
* Device cover opening view
* Chip structure and material analysis
- Murata IMU:SCHA634
* Overview of physical analysis
* Device package view
* Device cover opening view
* Chip structure and material analysis
- TDK InvenSense IMU：IAM-20685
* Overview of physical analysis
* Device package view
* Device cover opening view
* Chip structure and material analysis
4. vs. 2015: SMI240 vs. SCHA634 vs. IAM-20685
- Comprehensive comparative analysis
- Comparative performance analysis
- Package comparison analysis
- Chip-to-chip comparative analysis
- Comparative analysis of manufacturing processes
- Comparative analysis of packaging processes
5. Patent-to-product mapping analysis
- Analyze processes and methods
- An overview of the company's patents
- Patent-to-product mapping
* Mapping of Bosch patents to products
* Murata patent-to-product mapping
* TDK InvenSense专利到产品的映射
If you need to purchase the report "Comparative Analysis of Automotive-grade MEMS Inertial Measurement Unit (IMU) Products-2024 Edition", please contact Wang Yi of MEMS Consulting, email :wangyi#memsconsulting.com (#换成@)