Automotive Battery Management Systems

The ADBMS6832/ADBMS6833 are multicell battery stack monitors that measure series-connected battery cells with a lifetime total measurement error (TME) of less than 2 mV over the full temperature range. ADBMS6832 can measure up to 18 and ADBMS6833 up to 16 series connected cells. The measurement input range of −2 V to +5.5 V makes the ADBMS6832/ADBMS6833 suitable for most battery chemistries and allows the measurement of voltages across bus bars. Provisions are made for bypassing bus bars without dedicating any measurement channels.

All cells can be measured simultaneously and redundantly with two individual analog-to-digital converters (ADCs), which operate with a high sampling rate of 4.096 MHz, allowing reduced external analog filtering and aliasing-free measurement results. Higher noise reduction can be achieved by subsequent programmable infinite impulse response (IIR) filters. Multiple ADBMS6832/ADBMS6833s can be connected in series, permitting simultaneous cell monitoring of long, high-voltage battery strings. Each ADBMS6832/ADBMS6833 has an isolated serial port interface (isoSPI^™) for high-speed, RF-immune, long-distance communication. Multiple devices are connected in a daisy chain with one host processor connection, which can be operated bidirectionally, ensuring communication integrity even in the event of a fault along the communication path.

The ADBMS6832/ADBMS6833 can be powered from the battery stack or an isolated supply. They include passive balancing with individual pulse-width modulation (PWM) duty cycle control and up to 300 mA discharge current for each cell. Other features include an on-board 5 V regulator, up to 10 GPIOs, and a sleep mode, where current consumption is reduced to 4 μA.

APPLICATIONS

• Electric and hybrid electric vehicles
• Backup battery systems
• Grid energy storage

The ADBMS6832/ADBMS6833 are multicell battery stack monitors that measure series-connected battery cells with a lifetime total measurement error (TME) of less than 2 mV over the full temperature range. ADBMS6832 can measure up to 18 and ADBMS6833 up to 16 series connected cells. The measurement input range of −2 V to +5.5 V makes the ADBMS6832/ADBMS6833 suitable for most battery chemistries and allows the measurement of voltages across bus bars. Provisions are made for bypassing bus bars without dedicating any measurement channels.

All cells can be measured simultaneously and redundantly with two individual analog-to-digital converters (ADCs), which operate with a high sampling rate of 4.096 MHz, allowing reduced external analog filtering and aliasing-free measurement results. Higher noise reduction can be achieved by subsequent programmable infinite impulse response (IIR) filters. Multiple ADBMS6832/ADBMS6833s can be connected in series, permitting simultaneous cell monitoring of long, high-voltage battery strings. Each ADBMS6832/ADBMS6833 has an isolated serial port interface (isoSPI^™) for high-speed, RF-immune, long-distance communication. Multiple devices are connected in a daisy chain with one host processor connection, which can be operated bidirectionally, ensuring communication integrity even in the event of a fault along the communication path.

The ADBMS6832/ADBMS6833 can be powered from the battery stack or an isolated supply. They include passive balancing with individual pulse-width modulation (PWM) duty cycle control and up to 300 mA discharge current for each cell. Other features include an on-board 5 V regulator, up to 10 GPIOs, and a sleep mode, where current consumption is reduced to 4 μA.

APPLICATIONS

• Electric and hybrid electric vehicles
• Backup battery systems
• Grid energy storage

The ADRF8801/ADRF8851 are low-power, integrated systems on chip (SoC) that include a 2.4 GHz industrial scientific medical (ISM) band radio and an embedded microcontroller unit (MCU) subsystem.

The ADRF8801/ADRF8851 provide wireless communications between the battery cell monitoring chip and the battery management system (BMS) controller. In the wireless battery management system (wBMS), the ADRF8801 nodes reside at the battery cells and receive sensor data from the battery cell monitors. The nodes send the data over the air to an ADRF8851 network manager, and the manager provides the data to the BMS controller. The ADRF8851 network manager configures the network of nodes and manages the communications protocol.

The embedded MCUs integrate static random access memory (SRAM), embedded flash memory, one-time programmable (OTP) memory, and an analog subsystem that provides clocking and reset.

The ADRF8801/ADRF8851 has a rich set of peripherals, including serial peripheral interface (SPI), general-purpose input and output (GPIOs) ports, universal asynchronous receiver/transmitter (UART), and Joint Test Action Group (JTAG) port, as well as a temperature sensor.

The ADRF8801/ADRF8851 provide secure boot using software stored in read-only memory (ROM) that authenticates the next boot stage using a hardware accelerated 256-bit elliptic curve cryptography (ECC-256) engine. Other hardware-accelerated cryptographic features include the 128-bit advanced encryption standard (AES-128), 256-bit advanced encryption standard (AES-256), and secure hash algorithm 256 (SHA-256). The ADRF8801/ADRF8851 have protected key storage with a root encrypted key generated on-chip that is only accessible to the on-chip hardware. The devices incorporate a true random number generator (TRNG) that is used to seed a National Institute of Standards and Technology (NIST) certified deterministic random bit generator (DRBG). The ADRF8801/ADRF8851 also include support for secure firmware updates with rollback protection. The in-field OTP memory is included to enforce the access control of debug ports and memory access once a device is ready for deployment.

The ADRF8801/ADRF8851 feature on-chip, low-dropout (LDO) regulators that allow the devices to be powered by a single 3.3 V nominal supply, provided by an external power management IC (PMIC) either stepping down from a high-voltage bus or a 12 V battery.

Each ADRF8801/ADRF8851 uses a single 40 MHz crystal to provide precision timing for the system.

The ADRF8801/ADRF8851 are available in a 7 mm × 7 mm body size, 48-lead LQFP_EP package, measuring 9 mm × 9 mm when leads are included.

APPLICATIONS

• Wireless Battery Management Systems

The ADRF8801/ADRF8851 are low-power, integrated systems on chip (SoC) that include a 2.4 GHz industrial scientific medical (ISM) band radio and an embedded microcontroller unit (MCU) subsystem.

The ADRF8801/ADRF8851 provide wireless communications between the battery cell monitoring chip and the battery management system (BMS) controller. In the wireless battery management system (wBMS), the ADRF8801 nodes reside at the battery cells and receive sensor data from the battery cell monitors. The nodes send the data over the air to an ADRF8851 network manager, and the manager provides the data to the BMS controller. The ADRF8851 network manager configures the network of nodes and manages the communications protocol.

The embedded MCUs integrate static random access memory (SRAM), embedded flash memory, one-time programmable (OTP) memory, and an analog subsystem that provides clocking and reset.

The ADRF8801/ADRF8851 has a rich set of peripherals, including serial peripheral interface (SPI), general-purpose input and output (GPIOs) ports, universal asynchronous receiver/transmitter (UART), and Joint Test Action Group (JTAG) port, as well as a temperature sensor.

The ADRF8801/ADRF8851 provide secure boot using software stored in read-only memory (ROM) that authenticates the next boot stage using a hardware accelerated 256-bit elliptic curve cryptography (ECC-256) engine. Other hardware-accelerated cryptographic features include the 128-bit advanced encryption standard (AES-128), 256-bit advanced encryption standard (AES-256), and secure hash algorithm 256 (SHA-256). The ADRF8801/ADRF8851 have protected key storage with a root encrypted key generated on-chip that is only accessible to the on-chip hardware. The devices incorporate a true random number generator (TRNG) that is used to seed a National Institute of Standards and Technology (NIST) certified deterministic random bit generator (DRBG). The ADRF8801/ADRF8851 also include support for secure firmware updates with rollback protection. The in-field OTP memory is included to enforce the access control of debug ports and memory access once a device is ready for deployment.

The ADRF8801/ADRF8851 feature on-chip, low-dropout (LDO) regulators that allow the devices to be powered by a single 3.3 V nominal supply, provided by an external power management IC (PMIC) either stepping down from a high-voltage bus or a 12 V battery.

Each ADRF8801/ADRF8851 uses a single 40 MHz crystal to provide precision timing for the system.

The ADRF8801/ADRF8851 are available in a 7 mm × 7 mm body size, 48-lead LQFP_EP package, measuring 9 mm × 9 mm when leads are included.

APPLICATIONS

• Wireless Battery Management Systems

The ADBMS2950 and ADBMS2952 are battery pack monitors, and the ADBMS2951 is a link monitor for electrical and hybrid vehicles, and other current or voltage sense applications. The ADBMS2950 and ADBMS2952 measure the current flowing in and out of a battery pack by sensing the voltage drop over a shunt resistor with a very low offset.

The ADBMS2950 and ADBMS2952 also detect overcurrent conditions using fast overcurrent ADCs with digital threshold comparators and communicate their results through dedicated overcurrent alert lines with minimum delay.

The ADBMS2950/ADBMS2951/ADBMS2952 feature a total of 12 internally buffered high impedance inputs for measuring voltages from external sensors or resistor dividers, enabling measurement of pack voltages, temperatures, HV-Link voltages, chassis isolation, and the supervision of the state of contactors and fuses.

Six digital outputs (GPOs) supporting open-drain or push-pull can be used to control high voltage transistors to disconnect external resistor dividers. Four digital GPIOs also allow operation as an I²C or SPI controller interface to address an external EEPROM or other serial peripherals.

The built-in serial interface of the ADBMS2950 and ADBMS2951 can be configured for SPI or isolated isoSPI communication to the host. An additional isoSPI port allows to connect a daisy-chain of the ADBMS2950 and ADBMS2951 devices; optionally extended with the ADBMS683x cell monitors. The ADBMS2952 supports SPI communication only.

Applications

• Electric and hybrid electric vehicles
• Backup battery systems
• Grid energy storage