How strong is ADI's BMS product? This speech tells the story

In his opinion, the biggest advantage of ADI BMS products lies in the management accuracy of lithium batteries. No matter what environment they are in, the accuracy error can be controlled within a very small range and can remain unchanged for ten years. This allows car manufacturers and battery suppliers to boldly use its battery capacity without being hesitant due to insufficient accuracy, and can also improve the overall range of electric vehicles with the same battery capacity. "This achievement is mainly due to the fact that ADI BMS products have a technology called Buried Zener Reference embedded in them, which is a very stable reference source that can provide very precise characteristics for the measurement system." Wang Cheng added.

In his speech, Wang Cheng focused on the ADI battery pack monitor LTC681X series . ADI's fourth-generation lithium battery pack monitoring IC product LTC6811 is a complete battery measurement device for hybrid/electric vehicles. It can measure the voltage of up to 12 series-connected batteries with an accuracy better than 0.04%. Multiple LTC6811s can be connected in a daisy chain. The IC also provides the industry's fastest conversion speed and best data protection.

In addition, as OEMs become more and more sensitive to the lightweight and cost reduction of power batteries, in order to further promote the development of electric vehicles, ADI launched a wireless BMS, which removes the cable connection of the car, reduces the weight of the car, reduces the complexity of the system, and increases the reliability of the system. Because whether it is a CAN bus or an isoSPI bus, the battery monitoring chip is connected in series in a daisy chain manner. Once a problem occurs in a connection, the entire system will be paralyzed, while a wireless communication BMS can reduce the risk of connector failure, and a single point of failure has limited impact on the overall system.

As we all know, according to the demand for battery management in new energy vehicles, BMS has functions including SOC/SOH estimation, fault diagnosis, balancing control, thermal management and charging management. The functional safety standard defined by ISO26262 covers the stages of product management, development, production, operation, service and scrapping, covering the entire life cycle of the product. The main stages of product development are concept, system-level development, hardware development and software development. In the functional safety concept stage, system hazard analysis and risk assessment should be conducted to derive the automotive safety integrity level ASIL (Automotive Safety Integrity Level). The ISO26262 standard specifies four safety levels from A to D, of which D is the highest level and the corresponding requirements are the most stringent.

After the safety level ASIL is obtained, it is necessary to set a safety goal , propose corresponding safety requirements and safety mechanisms , and perform functional safety level decomposition when necessary. According to Wang Cheng, in general, mainstream car manufacturers believe that the safety level that BMS should achieve is at least ASIL-C. When developing ADI's BMS products, its functional safety was fully verified from multiple aspects such as signal acquisition diagnosis, temperature monitoring, and FTTI, and a diagnostic coverage method for external device failures was provided, setting an industry standard for high-performance and high-reliability BMS systems.

In addition to displaying the BMS system, ADI also displayed innovative vehicle audio A2B bus technology and vehicle camera C2B bus technology at the conference, fully demonstrating ADI's long-term layout and strong strength in the field of automotive electronics.