The ADBMS6948 by Analog Devices is a high-precision, 16-channel battery pack monitor designed for precise and reliable multi-cell battery management. It can monitor up to 16 series-connected cells with a total measurement error (TME) of less than 3mV across the entire temperature range and lifetime. The system features redundant measurement capabilities for voltage, current, and temperature, ensuring high accuracy and reliability. It utilizes two analog-to-digital converters (ADCs) with a sampling rate of 4.096MHz, allowing simultaneous and redundant cell voltage measurements. With features like parallel measurement architecture, fast sampling rate, and integrated coulomb counter, it provides precise state-of-charge, power, and health estimation. Advanced overcurrent detection and low-power monitoring ensure battery safety and system efficiency. Ideal for automotive, energy storage, and other battery-powered systems, the ADBMS6948 ensures optimal battery performance and safety.   

ADBMS6948 Battery Pack Monitoring System Features  

ADBMS6948 is a high-precision, 16-channel battery pack monitoring system designed for demanding applications. Offering exceptional accuracy and reliability, it provides critical data for optimal battery performance and safety. Let’s explore its notable features:

Precise Voltage and Current Measurement

The ADBMS6948 offers high-precision monitoring of up to 16 series-connected battery cells. Its parallel and redundant measurement architecture ensures accurate voltage readings with a total measurement error (TME) of less than 2 mV at 4.2 V. Simultaneous and redundant cell voltage measurements are enabled by two independent analog-to-digital converters (ADCs). The integrated bidirectional current measurement capability, with an input offset voltage of 1 µV and a 0.1% gain error, ensures precise current readings. This data is crucial for accurate state-of-charge (SOC), state-of-power (SOP), and state-of-health (SOH) estimations.

Overcurrent Detection and Protection

Rapid and reliable overcurrent (OC) detection is a core feature of the ADBMS6948. With a response time under 2 µs, the device effectively prevents false alarms and missed OC events. The system includes dedicated overcurrent pins for controlling external switches or MOSFETs, ensuring quick and efficient protection against overcurrent conditions. The overcurrent detection algorithm, based on energy calculations, accurately identifies OC conditions even under challenging circumstances like short-duration glitches or high load conditions.

Comprehensive Low Power Monitoring

The ADBMS6948 prioritizes battery safety with its low power monitoring (LPM) mode. Key battery parameters, including cell voltage, temperature, and pack current, are continuously monitored, even when the main system is in sleep mode. The system can detect early signs of thermal runaway by tracking the rate of change in voltage (dV/dt), temperature (dT/dt), and current (dI/dt). The device generates an interrupt when pre-defined thresholds are exceeded, allowing timely corrective actions. 

Flexible Integration and Control

Designed for seamless integration, the ADBMS6948 communicates via a 4-wire SPI interface operating at up to 4 MHz. This facilitates fast and reliable communication for configuration, measurement triggering, and data readback. Its compact 64-pin QFN-SS package and AEC-Q100 qualification make it suitable for demanding automotive and industrial applications. Additional features include passive cell balancing, an onboard 5V regulator, and flexible GPIO channels, enhancing system versatility.   

The ADBMS6948 is designed with a strong emphasis on redundancy and reliability. The parallel measurement architecture for both voltage and current ensures that even if one component fails, the system can continue to operate with reduced accuracy. This redundancy is critical in applications where system uptime is paramount, such as in automotive and energy storage systems.

Applications

The high precision, reliability, and advanced features of ADBMS6948 make it suitable for various battery-intensive applications. Its primary applications include electric vehicle powertrains, encompassing mild hybrid, two-wheeler, and three-wheeler platforms. In the two-wheeler and three-wheeler electric vehicle segment, it ensures optimal battery performance and extends battery life. For four-wheeler electric vehicles, the ADBMS6948 is well-suited for auxiliary battery management, providing critical data for energy management systems. Additionally, its capabilities extend to backup power systems and stationary energy storage systems (ESS), safeguarding against overcharge, over-discharge, and other potential hazards.