ZHCSGY5A October   2017  – December 2017

PRODUCTION DATA.  

  1. 1 特性
  2. 2 应用范围
  3. 3 说明
    1.     典型应用电路
  4. 4 修订历史记录
  5. 5 说明 （续）
  6. 6 Device Comparison Table
  7. 7 Pin Configuration and Functions
    1.     Pin Functions
    2. 7.1 EN1/EN2 Settings
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Dissipation Ratings
    6. 8.6 Electrical Characteristics
    7. 8.7 Typical Characteristics
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Undervoltage Lockout (UVLO)
      2. 9.3.2 Power On
      3. 9.3.3 Overvoltage Protection (OVP)
      4. 9.3.4 Dynamic Power-Path Management
        1. 9.3.4.1 Input Source Connected (ADAPTER or USB)
          1. 9.3.4.1.1 Input DPM Mode (VIN-DPM)
          2. 9.3.4.1.2 DPPM Mode
          3. 9.3.4.1.3 Battery Supplement Mode
        2. 9.3.4.2 Input Source Not Connected
      5. 9.3.5 Battery Charging
        1. 9.3.5.1 Charge Current Translator
        2. 9.3.5.2 Battery Detection and Recharge
        3. 9.3.5.3 Battery Disconnect (SYSOFF Input, bq24076, bq24078)
        4. 9.3.5.4 Dynamic Charge Timers (TMR Input)
        5. 9.3.5.5 Status Indicators (PGOOD, CHG)
        6. 9.3.5.6 Thermal Regulation and Thermal Shutdown
      6. 9.3.6 Battery Pack Temperature Monitoring
    4. 9.4 Device Functional Modes
      1. 9.4.1 Sleep Mode
      2. 9.4.2 Explanation of Deglitch Times and Comparator Hysteresis
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 bq2407x Charger Design Example
          1. 10.2.2.1.1 System ON/OFF (SYSOFF) (bq24076 or bq24078 only)
        2. 10.2.2.2 Calculations
          1. 10.2.2.2.1 Program the Fast Charge Current (ISET):
          2. 10.2.2.2.2 Program the Input Current Limit (ILIM)
          3. 10.2.2.2.3 Program 6.25-hour Fast-Charge Safety Timer (TMR)
        3. 10.2.2.3 TS Function
        4. 10.2.2.4 CHG and PGOOD
        5. 10.2.2.5 Selecting IN, OUT, and BAT Pin Capacitors
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
    3. 12.3 Thermal Considerations
  13. 13器件和文档支持
    1. 13.1 器件支持
      1. 13.1.1 Third-Party Products Disclaimer
    2. 13.2 相关链接
    3. 13.3 接收文档更新通知
    4. 13.4 社区资源
    5. 13.5 商标
    6. 13.6 静电放电警告
    7. 13.7 Glossary
  14. 14机械、封装和可订购信息

封装选项

机械数据 (封装 | 引脚)
散热焊盘机械数据 (封装 | 引脚)
订购信息

9.3.6 Battery Pack Temperature Monitoring

The bq2407x features an external battery pack temperature monitoring input. The TS input connects to the NTC thermistor in the battery pack to monitor battery temperature and prevent dangerous over-temperature conditions. During charging, INTC is sourced to TS and the voltage at TS is continuously monitored. If, at any time, the voltage at TS is outside of the operating range (VCOLD to VHOT), charging is suspended. The timers maintain their values but suspend counting. When the voltage measured at TS returns to within the operation window, charging is resumed and the timers continue counting. When charging is suspended due to a battery pack temperature fault, the CHG pin remains low and continues to indicate charging.

For applications that do not require the TS monitoring function, connect a 10-kΩ resistor from TS to VSS to set the TS voltage at a valid level and maintain charging.

The allowed temperature range for 103AT-2 type thermistor is 0°C to 50°C. However, the user may increase the range by adding two external resistors. See Figure 20 for the circuit details. The values for Rs and Rp are calculated using the following equations:

Equation 6. bq24076 bq24078 EQ2_rs_lus810.gif
Equation 7. bq24076 bq24078 EQ3_rp_lus810.gif

where

  • RTH: Thermistor Hot Trip Value found in thermistor data sheet
  • RTC: Thermistor Cold Trip Value found in thermistor data sheet
  • VH: IC's Hot Trip Threshold = 0.3 V nominal
  • VC: IC's Cold Trip Threshold = 2.1 V nominal
  • ITS: IC's Output Current Bias = 75 µA nominal
  • NTC Thermsitor Semitec 103AT-4

Rs and Rp 1% values were chosen closest to calculated values in Table 3.

Table 3. Calculated Values

COLD TEMP RESISTANCE AND TRIP THRESHOLD, Ω (°C)HOT TEMP RESISTANCE AND TRIP THRESHOLD, Ω (°C)EXTERNAL BIAS RESISTOR, Rs (Ω)EXTERNAL BIAS RESISTOR, Rp (Ω)
28000 (–0.6) 4000 (51) 0 ∞
28480 (–1) 3536 (55) 487 845000
28480 (–1) 3021 (60) 1000 549000
33890 (–5) 4026 (51) 76.8 158000
33890 (–5) 3536 (55) 576 150000
33890 (–5) 3021 (60) 1100 140000

RHOT and RCOLD are the thermistor resistance at the desired hot and cold temperatures, respectively. The temperature window cannot be tightened more than using only the thermistor connected to TS, it can only be extended.

bq24076 bq24078 ts_circuit_luscm1.gifFigure 20. Extended TS Pin Thresholds