SLUSE42A july   2020  – april 2023 BQ21062

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Description (continued)
  6. Device Comparison Table
  7. Pin Configuration and Functions
  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 Electrical Characteristics
    6. 8.6 Timing Requirements
    7. 8.7 Typical Characteristics
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Linear Charger and Power Path
        1. 9.3.1.1 Battery Charging Process
        2. 9.3.1.2 JEITA and Battery Temperature Dependent Charging
        3. 9.3.1.3 Input Voltage Based Dynamic Power Management (VINDPM)
        4. 9.3.1.4 Battery Supplement Mode
      2. 9.3.2  Protection Mechanisms
        1. 9.3.2.1 Input Over-Voltage Protection
        2. 9.3.2.2 Safety Timer and I2C Watchdog Timer
        3. 9.3.2.3 Thermal Protection and Thermal Charge Current Foldback
        4. 9.3.2.4 Battery Short and Over Current Protection
        5. 9.3.2.5 PMID Short Circuit
      3. 9.3.3  VDD LDO
      4. 9.3.4  Load Switch/LDO Output and Control
      5. 9.3.5  PMID Power Control
      6. 9.3.6  System Voltage (PMID) Regulation
      7. 9.3.7  MR Wake and Reset Input
        1. 9.3.7.1 MR Wake or Short Button Press Functions
        2. 9.3.7.2 MR Reset or Long Button Press Functions
      8. 9.3.8  14-Second Watchdog for HW Reset
      9. 9.3.9  Faults Conditions and Interrupts ( INT)
        1. 9.3.9.1 Flags and Fault Condition Response
      10. 9.3.10 Power Good ( PG) Pin
      11. 9.3.11 External NTC Monitoring (TS)
        1. 9.3.11.1 TS Thresholds
      12. 9.3.12 I2C Interface
        1. 9.3.12.1 F/S Mode Protocol
    4. 9.4 Device Functional Modes
      1. 9.4.1 Ship Mode
      2. 9.4.2 Low Power
      3. 9.4.3 Active Battery
      4. 9.4.4 Charger/Adapter Mode
      5. 9.4.5 Power-Up/Down Sequencing
    5. 9.5 Register Map
      1. 9.5.1 I2C Registers
  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 Input (IN/PMID) Capacitors
        2. 10.2.2.2 VDD, LDO Input and Output Capacitors
        3. 10.2.2.3 TS
        4. 10.2.2.4 Recommended Passive Components
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Third-Party Products Disclaimer
    2. 13.2 Documentation Support
      1. 13.2.1 Related Documentation
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 Support Resources
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

Battery Charging Process

The following diagram summarizes the charging process of the BQ21062 charger.

GUID-98A66C7B-A773-48CD-8270-587BB4858E4F-low.gifFigure 9-1 BQ21062 Charger Flow Diagram

When a valid input source is connected (VIN > VUVLO and VBAT+VSLP < VIN < VOVP), the state of the CE pin determines whether a charge cycle is initiated. When the CE input is high and a valid input source is connected, the battery charge FET is turned off, preventing any kind of charging of the battery. A charge cycle is initiated when the CHARGE_DISABLE bit is written to 0 and CE pin in low. Table 9-1 shows the CE pin and bit priority to enable/disable charging.

Table 9-1 Charge Enable Function Through CE Pin and CE Bit
CE PINCHARGE _DISABLE BITCHARGING
00Enabled
01Disabled
10Disabled
11Disabled

Figure 9-2 shows a typical charge cycle.

GUID-AFEC53C3-301D-41E1-9DF6-06FF71A9E21A-low.pngFigure 9-2 BQ21062 Typical Charge Cycle

During Pre-Charge, where the battery voltage is below the VLOWV level, the battery willl be charge with IPRECHARGE current which can be programmed through I2C. During pre-charge, the safety timer is set to 25% of the safety timer value during fast charge. Once the battery voltage reaches VLOWV, the charger will then operate in Fast Charge Mode, charging the battery at ICHARGE which may also be programmed through I2C. Once the battery voltage approaches the VBATREG level, the charging current starts tapering off as shown in Figure 9-2. Once the charging current reaches the termination current (ITERM) charging is stopped. Note that to ensure that the battery is charged to VBATREG level, the regulated PMID voltage should be set to at least 200mV above VBATREG. Termination is only enabled when the charger CV loop is active in fast charge operation. No termination will occur if the charge current reaches ITERM while VINDPM is active as well as the thermal regulation loop. Termination is also disabled when operating in the TS WARM region. The charger only goes to termination when the current drops to ITERM due to the battery reaching the target voltage and not due to the charge current limitation imposed by the previously mentioned control loops

Whenever a change in the charge current setting is triggered, whether it occurs due to I2C programming by the host, Pre-Charge/Fast Charge transition or JEITA TS control, the device will temporarily disable charging (for ~ 1 ms) before updating the charge current value.