12-Channel, High-Voltage Data-Acquisition Systems

The MAX17823H is a data acquisition system for the management of high-voltage battery modules. The system features a 12-bit SAR ADC that can measure 12 cell voltages and two temperatures in 161 µs. There are 12 internal switches for cell-balancing and extensive built-in diagnostics. Up to 32 devices can be daisy-chained together to manage 384 cells and monitor 64 temperatures.

Cell voltages (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. The system can shut itself down in the event of a thermal overload by measuring its own die temperature.

The system uses Maxim’s battery-management UART protocol for robust communications and, when used in conjunction with the MAX17880 12-channel battery monitor, is ideal for automotive battery-management systems that require a high safety-integrity level.

Applications

* Battery-Backup Systems (UPS) * Battery-Powered Tools * Electric Bikes * Electric Vehicles (EVs) * High-Voltage Battery Stacks * Hybrid Electric Vehicles (HEVs) * Super-Cap Systems

* AEC-Q100 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 Overvoltage Faults

* 12 Undervoltage Faults

* 2 Overtemperature Faults

* 2 Undertemperature 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)