JAJSL30 July   2023 ADS131B24-Q1

PRODUCTION DATA  

  1.   1
  2. 特長
  3. アプリケーション
  4. 概要
  5. Revision History
  6. 概要 (続き)
  7. Pin Configuration and Functions
  8. Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Switching Characteristics
    8. 7.8 Timing Diagram
    9. 7.9 Typical Characteristics
  9. Parameter Measurement Information
    1. 8.1 Offset Drift Measurement
    2. 8.2 Gain Drift Measurement
    3. 8.3 Noise Performance
  10. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Naming Conventions
      2. 9.3.2 Precision Voltage References (REFA, REFB)
      3. 9.3.3 Clocking (MCLK, OSCM, OSCD)
      4. 9.3.4 ADC1y
        1. 9.3.4.1 ADC1y Input Multiplexer
        2. 9.3.4.2 ADC1y Programmable Gain Amplifier (PGA)
        3. 9.3.4.3 ADC1y ΔΣ Modulator
        4. 9.3.4.4 ADC1y Digital Filter
        5. 9.3.4.5 ADC1y Offset and Gain Calibration
        6. 9.3.4.6 ADC1y Conversion Data
      5. 9.3.5 ADC2y
        1. 9.3.5.1 ADC2y Input Multiplexer
        2. 9.3.5.2 ADC2y Programmable Gain Amplifier (PGA)
        3. 9.3.5.3 ADC2y ΔΣ Modulator
        4. 9.3.5.4 ADC2y Digital Filter
        5. 9.3.5.5 ADC2y Offset and Gain Calibration
        6. 9.3.5.6 ADC2y Sequencer
        7. 9.3.5.7 VCMy Buffers
        8. 9.3.5.8 ADC2y Measurement Configurations
        9. 9.3.5.9 ADC2y Conversion Data
      6. 9.3.6 General-Purpose Digital Inputs and Outputs (GPIO0 to GPIO4)
        1. 9.3.6.1 GPIOx PWM Output Configuration
        2. 9.3.6.2 GPIOx PWM Input Readback
      7. 9.3.7 General-Purpose Digital Inputs and Outputs (GPIO0A, GPIO1A, GPIO0B, GPIO1B)
      8. 9.3.8 Monitors and Diagnostics
        1. 9.3.8.1  Supply Monitors
        2. 9.3.8.2  Clock Monitors
        3. 9.3.8.3  Digital Monitors
          1. 9.3.8.3.1 Register Map CRC
          2. 9.3.8.3.2 Memory Map CRC
          3. 9.3.8.3.3 GPIO Readback
        4. 9.3.8.4  Communication Monitors
        5. 9.3.8.5  Fault Flags and Fault Masking
        6. 9.3.8.6  FAULT Pin
        7. 9.3.8.7  Diagnostics and Diagnostic Procedure
        8. 9.3.8.8  Indicators
        9. 9.3.8.9  Conversion and Sequence Counters
        10. 9.3.8.10 Supply Voltage Readback
        11. 9.3.8.11 Temperature Sensors (TSA, TSB)
        12. 9.3.8.12 Test DACs (TDACA, TDACB)
        13. 9.3.8.13 Open-Wire Detection
        14. 9.3.8.14 Missing Host Detection and MHD Pin
        15. 9.3.8.15 Overcurrent Comparators (OCCA, OCCB)
          1. 9.3.8.15.1 OCCA and OCCB Pins
          2. 9.3.8.15.2 Overcurrent Indication Response Time
    4. 9.4 デバイスの機能モード
      1. 9.4.1 Power-Up and Reset
        1. 9.4.1.1 Power-On Reset (POR)
        2. 9.4.1.2 RESETn Pin
        3. 9.4.1.3 RESET Command
      2. 9.4.2 Operating Modes
        1. 9.4.2.1 Active Mode
        2. 9.4.2.2 Standby Mode
        3. 9.4.2.3 Power-Down Mode
      3. 9.4.3 ADC Conversion Modes
        1. 9.4.3.1 ADC1y Conversion Modes
          1. 9.4.3.1.1 Continuous-Conversion Mode
          2. 9.4.3.1.2 Single-Shot Conversion Mode
          3. 9.4.3.1.3 Global-Chop Mode
            1. 9.4.3.1.3.1 Overcurrent Indication Response Time in Global-Chop Mode
        2. 9.4.3.2 ADC2y Sequencer Operation and Sequence Modes
          1. 9.4.3.2.1 Continuous Sequence Mode
          2. 9.4.3.2.2 Single-Shot Sequence Mode
          3. 9.4.3.2.3 Synchronized Single-Shot Sequence Mode Based on ADC1y Conversion Starts
    5. 9.5 Programming
      1. 9.5.1 Serial Interface
        1. 9.5.1.1 Serial Interface Signals
          1. 9.5.1.1.1 Chip Select (CSn)
          2. 9.5.1.1.2 Serial Data Clock (SCLK)
          3. 9.5.1.1.3 Serial Data Input (SDI)
          4. 9.5.1.1.4 Serial Data Output (SDO)
          5. 9.5.1.1.5 Data Ready (DRDYn)
        2. 9.5.1.2 Serial Interface Communication Structure
          1. 9.5.1.2.1 SPI Communication Frames
          2. 9.5.1.2.2 SPI Communication Words
          3. 9.5.1.2.3 STATUS Word
          4. 9.5.1.2.4 Communication Cyclic Redundancy Check (CRC)
          5. 9.5.1.2.5 Commands
            1. 9.5.1.2.5.1 NULL (0000 0000 0000 0000b)
            2. 9.5.1.2.5.2 RESET (0000 0000 0001 0001b)
            3. 9.5.1.2.5.3 LOCK (0000 0101 0101 0101b)
            4. 9.5.1.2.5.4 UNLOCK (0000 0110 0101 0101b)
            5. 9.5.1.2.5.5 WREG (011a aaaa aaa0 0nnnb)
            6. 9.5.1.2.5.6 RREG (101a aaaa aaan nnnnb)
          6. 9.5.1.2.6 SCLK Counter
          7. 9.5.1.2.7 SPI Timeout
          8. 9.5.1.2.8 Reading ADC1A, ADC1B, ADC2A, and ADC2B Conversion Data
          9. 9.5.1.2.9 DRDYn Pin Behavior
    6. 9.6 Register Map
      1. 9.6.1 Registers
  11. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 Unused Inputs and Outputs
      2. 10.1.2 Minimum Interface Connections
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Current Shunt Measurement
        2. 10.2.2.2 Battery Pack Voltage Measurement
        3. 10.2.2.3 Shunt Temperature Measurement
        4. 10.2.2.4 Analog Output Temperature Sensor Measurement
      3. 10.2.3 Application Curves
    3. 10.3 Power Supply Recommendations
      1. 10.3.1 Power-Supply Options
        1. 10.3.1.1 Single Unregulated External 4-V to 16-V Supply (3.3-V Digital I/O Levels)
        2. 10.3.1.2 Single Regulated External 3.3-V Supply (3.3-V Digital IO Levels)
        3. 10.3.1.3 Single Regulated External 5-V Supply (5-V Digital I/O Levels)
      2. 10.3.2 Power-Supply Sequencing
      3. 10.3.3 Power-Supply Decoupling
    4. 10.4 Layout
      1. 10.4.1 Layout Guidelines
      2. 10.4.2 Layout Example
  12. 11デバイスおよびドキュメントのサポート
    1. 11.1 ドキュメントのサポート
      1. 11.1.1 関連資料
    2. 11.2 ドキュメントの更新通知を受け取る方法
    3. 11.3 サポート・リソース
    4. 11.4 商標
    5. 11.5 静電気放電に関する注意事項
    6. 11.6 用語集
  13. 12Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ(パッケージ|ピン)
サーマルパッド・メカニカル・データ
発注情報

Overview

The ADS131B24-Q1 is a fully integrated, high-voltage battery pack monitor for automotive electrical vehicle (EV) battery management systems (BMS) that integrates two simultaneous-sampling, high-precision, 24-bit ADC channels (ADC1A, ADC1B) to redundantly measure battery current with high resolution and accuracy using an external shunt resistor. Two independent digital overcurrent detection comparators (OCCA, OCCB) work in parallel to the two ADCs for fast overcurrent detection.

Additionally, two multiplexed, 16-bit ADC channels (ADC2A, ADC2B) are available to measure shunt temperature using external temperature sensors, such as thermistors or analog output temperature sensors, and other voltages in the system. ADC2A and ADC2B are equipped with channel sequencers that automatically step through the configured multiplexer inputs, select them for measurement, and start ADC conversions.

The device is partitioned into two sections, A and B. The circuitry in section A is independent from the circuitry in section B. However, both sections are powered from the same supply, derive their respective clocks from the same main clock source, and share the same digital control and serial interface.

Besides the various ADC channels, each section provides:

  • A precision, low-drift, 1.25-V voltage reference (REFA, REFB) that feeds the ADCs in each section
  • A negative charge pump (NCPA, NCPB) that provides a negative supply voltage for the gain stages in front of each ADC to allow signal measurements below ground
  • A temperature sensor (TSA, TSB) to measure die temperature through ADC2A and ADC2B, respectively
  • A Test DAC (Test DAC A, Test DAC B), which generates precision test voltages that can be routed for measurement to the ADCs in the other section
  • Two GPIOs (GPIO0A, GPIO1A and GPIO0B, GPIO1B) with logic levels based on AVDD

In many BMS applications, the pack monitor is powered from an unregulated isolated DC/DC converter. For that reason, the ADS131B24-Q1 integrates linear regulators (AVDD and IOVDD LDOs) that accept voltages between 4 V and 16 V and provide regulated 3.3-V analog and digital supply rails for the internal circuitry. The two low-dropout regulators (LDOs) can also provide a limited amount of current to external circuitry. A common use case is to power the primary side of a digital isolator, which isolates the SPI communication to a host microcontroller, with the IOVDD LDO output; see the ADS131B26Q1EVM-PDK Evaluation Module user guide.

The main clock for the ADS131B24-Q1 is either provided by the internal 8.192-MHz oscillator or by an external clock provided at the CLK pin.

A multitude of monitoring and diagnostic features are integrated in the device to mitigate and detect random hardware faults to aid in the development of functional safety BMS, such as:

  • Supply undervoltage, overvoltage, overtemperature, and oscillation monitors
  • Supply-voltage readback capability through ADC2A and ADC2B
  • A set of open-wire detection current sources and sinks per ADC
  • Clock monitors
  • Cyclic redundancy check (CRC), timeout monitor, and SCLK counter on the SPI to achieve high data integrity for the communication
  • Register and memory map CRC
  • ADC conversion and sequence counters

The device offers five GPIOs (GPIO0 through GPIO4) with logic levels based on IOVDD and optional pulse-width modulation (PWM) input and output capability. GPIO2 can alternatively be configured as a FAULT output, and GPIO3 and GPIO4 can be configured as overcurrent comparator outputs.

As shown in Table 9-1, the ADS131B2x-Q1 family consists of three devices that differ in the amount of integrated ADC channels.

Table 9-1 ADS131B2x-Q1 Device Family Comparison by Available ADC Channels
DEVICE ADC1A, ADC1B ADC2A ADC2B ADC3A, ADC3B
ADS131B23-Q1 Yes Yes No No
ADS131B24-Q1 Yes Yes Yes No
ADS131B26-Q1 Yes Yes Yes Yes