Data Acquisition System for High-Voltage Battery Modules with 12-Bit SAR ADC
The MAX17823H from Maxim Integrated is a data acquisition system for managing high-voltage battery modules. With a 12-bit SAR ADC, MAX17823H can measure 12 cell voltages and two temperatures in 161µs. It features 12 internal switches for cell-balancing and has extensive built-in diagnostics. Up to 32 devices can be daisy-chained to manage 384 cells and monitor 64 temperatures.
Applications for MAX17823H include battery-backup systems, battery-powered tools, electric bikes, EVs, high voltage battery stacks, supercapacitor systems, and related resources.
MAX17823H operates from 9V to 65V. It features an AECQ-100 Grade 2 temperature range of -40°C to 105°C.
Cell voltages of 0V to 5V are measured differentially over a 65V common-mode range. Cell measurements have a typical accuracy of 2mV (3.6V cell, 25°C). If oversampling is enabled, up to 128 measurements per channel can be averaged internally with 14-bit resolution.
It can sense thermal overload by measuring its die temperature, and then shut itself down. With ultra-low power operation, it uses 2mA in standby mode and 2µA in shutdown mode.
MAX17823H features built-in diagnostics to support ASIL-D and FMEA requirements.
The system uses the company’s battery-management UART protocol for robust communications, and when used in conjunction with the MAX17880 12-channel battery monitor, it is suitable for automotive battery-management systems that require a high safety-integrity level.
- AECQ-100 Grade 2 Temperature Range
- -40°C to 105°C
- Operating Voltage from 9V to 65V
- Ultra-Low Power Operation
- Standby Mode: 2mA
- Shutdown Mode: 2µA
- 12 Cell-Voltage Measurement Channels
- 2mV Accuracy (3.6V, +25°C)
- 5mV Accuracy (0°C to +45°C)
- 10mV Accuracy (-40°C to +105°C)
- 12 Cell-Balancing Switches
- Up to 650mA per switch
- Emergency Discharge Mode
- 2 Temperature Measurement Channels
- Die Temperature Measurement
- Automatic Thermal Protection
- 29 Voltage Threshold Alerts
- 12 Over-voltage Faults
- 12 Under-voltage Faults
- 2 Over-temperature Faults
- 2 Under-temperature Faults
- 1 Cell Mismatch Alert
- 4 GPIOs
- Built-in Diagnostics to Support ASIL-D and FMEA Requirements
- Battery-Management UART Protocol
- Daisy-Chain up to 32 Devices
- Communication Port Isolation
- Up to 2 Mbps Baud Rate (auto-detect)
- 1.5µs Propagation Delay per Device
- Packet-Error Checking (PEC)
- Factory-Trimmed Oscillators
- No External Crystals Required
- 10mm x 10mm Package (64-pin LQFP)