SLUSFB0 August   2024 BQ25758S

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Device Power-On-Reset
      2. 7.3.2 Device Power-Up From Battery Without Input Source
      3. 7.3.3 Device Power Up from Input Source
        1. 7.3.3.1 VAC Operating Window Programming (ACUV and ACOV)
        2. 7.3.3.2 MODE Pin Configuration
        3. 7.3.3.3 REGN Regulator (REGN LDO)
        4. 7.3.3.4 Switching Frequency and Synchronization (FSW_SYNC)
        5. 7.3.3.5 Device HIZ Mode
      4. 7.3.4 Power Management
        1. 7.3.4.1 Output Voltage Programming (VOUT_REG)
        2. 7.3.4.2 Output Current Programming (IOUT pin and IOUT_REG)
        3. 7.3.4.3 Dynamic Power Management: Input Voltage and Input Current Regulation
          1. 7.3.4.3.1 Input Current Regulation
            1. 7.3.4.3.1.1 IIN Pin
            2. 7.3.4.3.1.2 Multi-Level Current Limit (Overload Mode)
          2. 7.3.4.3.2 Input Voltage Regulation
        4. 7.3.4.4 Bypass Mode
      5. 7.3.5 Bidirectional Power Flow and Programmability
      6. 7.3.6 Integrated 16-Bit ADC for Monitoring
      7. 7.3.7 Status Outputs (PG, STAT and INT)
        1. 7.3.7.1 Power Good Indicator (PG)
        2. 7.3.7.2 Interrupt to Host (INT)
      8. 7.3.8 Protections
        1. 7.3.8.1 Voltage and Current Monitoring
          1. 7.3.8.1.1 VAC Over-voltage Protection (VAC_OVP)
          2. 7.3.8.1.2 VAC Under-voltage Protection (VAC_UVP)
          3. 7.3.8.1.3 Reverse Mode Over-voltage Protection (REV_OVP)
          4. 7.3.8.1.4 Reverse Mode Under-voltage Protection (REV_UVP)
          5. 7.3.8.1.5 DRV_SUP Under-voltage and Over-voltage Protection (DRV_OKZ)
          6. 7.3.8.1.6 REGN Under-voltage Protection (REGN_OKZ)
        2. 7.3.8.2 Thermal Shutdown (TSHUT)
      9. 7.3.9 Serial Interface
        1. 7.3.9.1 Data Validity
        2. 7.3.9.2 START and STOP Conditions
        3. 7.3.9.3 Byte Format
        4. 7.3.9.4 Acknowledge (ACK) and Not Acknowledge (NACK)
        5. 7.3.9.5 Target Address and Data Direction Bit
        6. 7.3.9.6 Single Write and Read
        7. 7.3.9.7 Multi-Write and Multi-Read
    4. 7.4 Device Functional Modes
      1. 7.4.1 Host Mode and Default Mode
      2. 7.4.2 Register Bit Reset
    5. 7.5 BQ25758S Registers
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Typical Application (Buck-Boost configuration)
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 ACUV / ACOV Input Voltage Operating Window Programming
          2. 8.2.1.2.2 Switching Frequency Selection
          3. 8.2.1.2.3 Inductor Selection
          4. 8.2.1.2.4 Input (VAC) Capacitor
          5. 8.2.1.2.5 Output (VBAT) Capacitor
          6. 8.2.1.2.6 Sense Resistor (RAC_SNS and RBAT_SNS) and Current Programming
          7. 8.2.1.2.7 Converter Fast Transient Response
        3. 8.2.1.3 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 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  13. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information
    1. 13.1 Packaging Information
    2. 13.2 Tape and Reel Information
    3. 13.3 Mechanical Data

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • RRV|36
Thermal pad, mechanical data (Package|Pins)

7.3.6 Integrated 16-Bit ADC for Monitoring

The device includes a 16-bit ADC to monitor critical system information based on the device’s modes of operation. The ADC is allowed to operate if either the VVAC>VVAC_OK or VBAT>VREGN_OK is valid. The ADC_EN bit provides the ability to enable and disable the ADC to conserve power. The ADC_RATE bit allows continuous conversion or one-shot behavior. After a one-shot conversion finishes, the ADC_EN bit is cleared, and must be re-asserted to start a new conversion.

The ADC_SAMPLE bits control the resolution and sample speed of the ADC. By default, ADC channels will be converted in one-shot or continuous conversion mode unless disabled in the ADC Function Disable register. If an ADC parameter is disabled by setting the corresponding bit, then the read-back value in the corresponding register will be from the last valid ADC conversion or the default POR value (all zeros if no conversions have taken place). If an ADC parameter is disabled in the middle of an ADC measurement cycle, the device will finish the conversion of that parameter, but will not convert the parameter starting the next conversion cycle. If all channels are disabled in one-shot conversion mode, the ADC_EN bit is cleared.

The ADC_DONE_STAT and ADC_DONE_FLAG bits signal when a conversion is complete in one-shot mode only. This event produces an INT pulse, which can be masked with ADC_DONE_MASK. During continuous conversion mode, the ADC_DONE_STAT bit has no meaning and will be '0'. The ADC_DONE_FLAG bit will remain unchanged in continuous conversion mode.

ADC conversion operates independently of the faults present in the device. ADC conversion will continue even after a fault has occurred (such as one that causes the power stage to be disabled), and the host must set ADC_EN = ‘0’ to disable the ADC. ADC readings are only valid for DC states and not for transients. When host writes ADC_EN = 0, the ADC stops immediately, and ADC measurement values correspond to last valid ADC reading.

If the host wants to exit ADC more gracefully, it is possible to do either of the following:

  1. Write ADC_RATE to one-shot, and the ADC will stop at the end of a complete cycle of conversions, or
  2. Disable all ADC conversion channels, and the ADC will stop at the end of the current measurement.

When system load is powered from the battery (input source is removed, or device in HIZ mode), enabling the ADC automatically powers up REGN and increases the quiescent current. To keep the battery leakage low, it is recommended to duty cycle or completely disable the ADC.