Analog Devices Inc. AD7284 Battery Monitoring System
Analog Devices Inc. AD7284 8-Channel, Li-Ion Battery Monitoring System includes all the functions required for the general-purpose monitoring of stacked Li-Ion batteries. The AD7284 features multiplexed cell voltage and auxiliary ADC measurement channels to support four to eight battery management cells. Designers can use the four auxiliary ADC input channels for temperature measurement or system diagnostics. The AD7284 can accommodate large common-mode signals across the full VDD range with eight differential analog input channels.
Analog Devices AD7284's design also includes two on-chip 2.5V voltage references. One voltage reference works with the primary measurement path, and the other is designated for the secondary measurement path. The integrated secondary measurement path validates the data on the primary 14-bit ADC. Other diagnostic features include the detection of open inputs, communication, and power-supply related faults.
The AD7284 offers a ±3mV maximum cell voltage accuracy, ±16mV typical battery stack voltage (TUE) accuracy, and very low measurement latency across 96 cells. The AD7284 Battery Monitoring System is ideal for li-ion battery monitoring, electric and hybrid electric vehicles, and stationary power applications.
Features
- 8 Analog Input Channels, Integrated Secondary Monitor
- ±3mV maximum cell voltage accuracy, TUE, 14-bit ADC
- Very low measurement latency across 96 cells
- Stack Voltage Measurement
- ±16mV typical battery stack voltage (TUE) accuracy
- Cell balancing interface, with individually programmable on time
- 4 Auxiliary Analog Input Channels, 14-bit ADC
- Suitable for thermistor inputs and external diagnostics
- Buffered reference output for ratiometric measurements
- Internal temperature sensor
- 10V to 40V operating range
- On-chip 5V regulator
- Watchdog timer
- 100μA IDD matching current
- Robust, proprietary daisy-chain interface
- SPI to host controller
- CRC protection on read and write commands
- 2 general-purpose outputs
- 64-lead low profile quad flat package, exposed pad (LQFP_EP)
- −30°C to +120°C junction temperature range
- Qualified for automotive applications
Applications
- Li-Ion battery monitoring
- Electric and hybrid electric vehicles
- Stationary power applications
Technical Article
A state-of-the-art battery monitoring system (BMS) not only allows the user to extract the highest quantity of charge from the battery pack but also lets them manage the charge and discharge cycles in a safer way, which results in an extended life. Analog Devices provides a full portfolio of BMS devices focusing on accuracy and robust operation.
EVAL-AD7284 Evaluation System
Analog Devices EVAL-AD7284 evaluation system includes separate master and slave evaluation kits for the AD7284 8-Channel, Li-Ion Battery Monitoring System. The kits provide designers with a direct current daisy chain or isolated daisy-chain options.
Block Diagram
