Second-generation six-axis IMUs for ADAS and safety applications

SmartAutomotive IAM-20685HP and IAM-20689 are second-generation 6-axis MEMS IMUs suited for safety-relevant automotive applications up to ASIL D

Compact in size and operating in a wide temperature range, they also seamlessly integrate into automotive modules for advanced driver assistance applications (ADAS)

Both IMUs can combine multiple applications within a single central unit, leveraging motion detection across all six directions

November 11, 2024

TDK Corporation has extended its InvenSense SmartAutomotive MEMS sensor family with the IAM-20685HP and IAM-20689 second-generation six-axis IMUs for automotive safety applications. Both devices provide reliable motion data for decision-making algorithms and accurately detect vehicle dynamics in real-time to enhance ADAS and safety applications, which need higher levels of functional safety up to ASIL D. Mass production of the devices has started, and samples are already available.

IAM-20685HP can achieve ASIL B on all technical safety requirements. It was specifically developed to enhance ADAS applications, e.g. to increase the driver’s experience while driving or parking. With its compact size and an operating temperature of up to 125C, the device is ideal for ADAS positioning and vision systems. Furthermore, it can be utilised in compact modules where high computational power combined with a small size requires high and stable IMU performance over a wide temperature range.

Compared to the IAM-20685HP, the IAM-20689 is a safety-focused six-axis IMU featuring extended embedded diagnostics. It has been created to meet systems with requirements up to ASIL D and to elevate safety in critical automotive applications, like electronic/roll stability control (ESC/RSC) and drive-by-wire (DbW).

While both components differ in ASIL, they share the same core design, package size, and register map, and include a diverse set of safety mechanisms that ensure real-time monitoring of sensor parameters. Embedded diagnostics eradicate the necessity for an external software library to reach the according functional safety level. This enables customers to easily integrate the devices into their applications.

“Thanks to the IAM-20689, TDK can offer more flexibility to automotive safety customers by eliminating the need for multiple three-axis sensors in the vehicle. This simplifies system complexity, enhances ease of use, and provides opportunities for miniaturisation”, says Alberto Marinoni, senior director of Product Marketing Automotive at InvenSense, a TDK Group company. “Most safety applications today rely on a limited number of axes, rendering current solutions partially blind and unable to gather all vehicle dynamics. Transitioning to a 6-axis solution ensures no motion information is missed, unlocking broader application possibilities for developers.”

The devices take advantage of the company's proprietary MEMS fabrication technology that delivers improved reliability compared to other MEMS fabrication technologies available. They have both been developed as a Safety Element out of Context (SEooC) and are automotive qualified according to AEC-Q100 grade 1. The sensors are available in a small 4.5mm × 4.5mm × 1.1mm³ QFN package with wettable flanks options that permit visual inspection at the end of the assembly line.