12-Channel High-Voltage Data Acquisition System

The MAX17823B is a data acquisition system for the management of high-voltage battery modules. The system features 12-bit SAR ADC that can measure 12 cell voltages and two temperatures in 161μs. 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 (0 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, they are ideal for automotive battery-management systems that require a high safety integrity level.

Applications

* Battery Packs * Battery Systems * Electric Bikes * Electric Vehicles and Hybrid Vehicle (HEV) * High-Power Battery Backup Systems * High-Voltage, Multi-Cell Series-Stacked- * Power Tools * SuperCap Backup 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 150mA per Switch

* Emergency-Discharge Mode

* Two Temperature-Measurement Channels

* Die Temperature Measurement

* Automatic Thermal Protection

* 29 Voltage Threshold Alerts

* 12 Over-Voltage Faults

* 12 Under-Voltage Faults

* Two Over-Temperature Faults

* Two Under-Temperature Faults

* One Cell Mismatch Alert (highest cell versus lowest cell)

* Four 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 2Mbps Baud Rate (Autodetect)

* 1.5&micros Propagation Delay per Device

* Packet-Error Checking (PEC)

* Factory-Trimmed Oscillators

* No External Crystals Required

* 10mm x 10mm Package (64-Pin LQFP)