SLUSFR2 November   2024 BQ21088

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Description (continued)
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Thermal Information
    4. 6.4 Recommended Operating Conditions
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
      1. 7.1.1 Battery Charging Process
        1. 7.1.1.1 Trickle Charge
        2. 7.1.1.2 Pre-Charge
        3. 7.1.1.3 Fast Charge
        4. 7.1.1.4 Termination
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Input Voltage Based Dynamic Power Management (VINDPM)
      2. 7.3.2  Dynamic Power Path Management Mode (DPPM)
      3. 7.3.3  Battery Supplement Mode
      4. 7.3.4  Sleep Mode
      5. 7.3.5  SYS Power Control (SYS_MODE bit control)
        1. 7.3.5.1 SYS Pulldown Control
      6. 7.3.6  SYS Regulation
      7. 7.3.7  ILIM Control
      8. 7.3.8  Protection Mechanisms
        1. 7.3.8.1 Input Overvoltage Protection
        2. 7.3.8.2 Battery Undervoltage Lockout
        3. 7.3.8.3 Battery Overcurrent Protection
        4. 7.3.8.4 System Overvoltage Protection
        5. 7.3.8.5 System Short Protection
        6. 7.3.8.6 Thermal Protection and Thermal Regulation
        7. 7.3.8.7 Safety Timer and Watchdog Timer
      9. 7.3.9  Pushbutton Wake and Reset Input
        1. 7.3.9.1 Pushbutton Wake or Short Button Press Functions
        2. 7.3.9.2 Pushbutton Reset or Long Button Press Functions
      10. 7.3.10 15-Second Timeout for HW Reset
      11. 7.3.11 Hardware Reset
      12. 7.3.12 Software Reset
      13. 7.3.13 Interrupt Indicator (/INT) Pin
      14. 7.3.14 External NTC Monitoring (TS)
        1. 7.3.14.1 TS Biasing and Function
      15. 7.3.15 I2C Interface
        1. 7.3.15.1 F/S Mode Protocol
    4. 7.4 Device Functional Modes
    5. 7.5 Register Maps
      1. 7.5.1 I2C Registers
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Application
      2. 8.2.2 Design Requirements
      3. 8.2.3 Detailed Design Procedure
      4. 8.2.4 Application Curves
  10. 9 Power Supply Recommendations
  11. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  12. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  13. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • YBG|8
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.3.11 Hardware Reset

The device is capable of hardware reset to completely powercycle the system. This is partcularly useful when a soft reset on the MCU or host fails to work. A hardware reset needs to be possible in all SYS MODES.

There are a few ways a hardware reset occurs. A hardware reset will occur when:

  1. The HW_RESET clock expires when the WATCHDOG_SEL is set to 0b01 or 0b10
  2. No I2C transaction occurs when VIN is plugged in when the WATCHDOG_15_SENABLE is set to 0b1 within 15s
  3. EN_RST_SHIP is set to 2b11
  4. PB_LPRESS_ACTION is set to 2b11 and the button has been pressed for a duration set by MR_LP_LPRESS

Below is a sequence of events during a hadware reset:

  1. Turn OFF (if adapter is present) input FET
  2. Turn OFF battery FET
  3. Engage pulldown on SYS
  4. Start the Autowake timer
  5. Once the Autowake timer expires, disconnect the pulldown on SYS
  6. Reset all registers to default (as in new power up)
  7. Turn ON battery FET and input FET (if applicable).

At a time tRESET_WARN before the reset pulldown on SYS occurs, an interrupt occurs to signify a hardware reset is about to occur.