Maxim's automotive battery-management system delivers highest level of safety

Designers of automotive battery-management systems (BMS) can now deliver the highest level of safety for voltage, current, temperature, and communication while also saving space and reducing solution cost, with Maxim Integrated Products‘ MAX17852 14-channel, high-voltage, ASIL-D data-acquisition system.

Designed for integration within electric vehicles, hybrid electric vehicles, and other transportation systems, the IC is ideal for smart junction box, 48V, and other automotive battery systems that can see voltages up to 400V and beyond.

“Enabling systems to achieve the highest level of safety (ASIL D) for a BMS system is really a must for consumers to feel safe in their electrified vehicles,” said Tamer Kira, executive director for the Automotive Business Unit at Maxim Integrated.

OEMs and electric vehicle manufacturers require that all battery systems meet the highest safety requirements set by the ISO26262 guidelines. Through comprehensive diagnostics and a safety-driven architecture, Maxim Integrated designed and manufactured the MAX17852 to enable customers to design their systems to meet the highest ASIL-D standards for voltage, current, temperature, and communication.

The small, cost-effective IC also offers the highest accuracy for delivering voltage, current, and temperature data with tight time synchronization. It allows a typical cell voltage measurement of ±0.45mV at room temperature and a maximum of ±2mV error in a temperature range of 5 to 40 degrees Celsius, enabling car OEMs to get the most mileage range out of their batteries.

With a current sense amplifier capability of ±300mV, and a gain setting up to 256 times, and 0.3 percent current sense gain error, the MAX17852 provides the fastest, most accurate data for calculating power management, state of health, and state of charge. The 14-channel battery, data-acquisition system integrates a current sense amplifier so that current information is acquired at the same time as cell voltage and temperature.

The MAX17852 allows both hall effect sensor and shunt resistors to be used as sensing components.

“The MAX17852 is the fastest and most accurate in voltage, current and temperature measurements and that is why it is the first battery data-acquisition system in the industry to achieve the highest safety rating for all the major components of a BMS system,” added Kira.

Advantages

Highest safety: ASIL-D rating for voltage, current, temperature, and communication enhances safety
Highest accuracy: Measurement accuracy with best current sense amplifier gain error to allow accurate, time-aligned current measurements to potentially boost mileage
Smaller size: High integration enables up to 16 percent smaller size than a discrete solution to save board space
Lower cost: Integrated current sense amplifier provides up to 20 percent cost savings
Versatility: The first device that can be adapted to many applications with voltage, current, and temperature sensing