SLUSFN3B July   2024  – November 2026 BQ25820

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 (BQ25820)
  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 Light-Load Operation
        5. 7.3.3.5 Switching Frequency and Synchronization (FSW_SYNC)
        6. 7.3.3.6 Device HIZ Mode
      4. 7.3.4 Battery Charging Management
        1. 7.3.4.1 Autonomous Charging Cycle
          1. 7.3.4.1.1 Charge Current Programming (ICHG pin and ICHG_REG)
        2. 7.3.4.2 Li-Ion Battery Charging Profile
        3. 7.3.4.3 LiFePO4 Battery Charging Profile
        4. 7.3.4.4 Charging Termination for Li-ion and LiFePO4
        5. 7.3.4.5 Charging Safety Timer
        6. 7.3.4.6 Thermistor Qualification
          1. 7.3.4.6.1 JEITA Guideline Compliance in Charge Mode
          2. 7.3.4.6.2 Cold/Hot Temperature Window in Reverse Mode
      5. 7.3.5 Power Path Management
        1. 7.3.5.1 Dynamic Power Management: Input Voltage and Input Current Regulation
          1. 7.3.5.1.1 Input Current Regulation
            1. 7.3.5.1.1.1 ILIM_HIZ Pin
          2. 7.3.5.1.2 Input Voltage Regulation
            1. 7.3.5.1.2.1 Max Power Point Tracking (MPPT) for Solar PV Panel
        2. 7.3.5.2 Ideal Diode BATFET Control
      6. 7.3.6 Reverse Mode Power Direction
      7. 7.3.7 Integrated 16-Bit ADC for Monitoring
      8. 7.3.8 Status Outputs (PG, STAT1, STAT2, and INT)
        1. 7.3.8.1 Power Good Indicator (PG)
        2. 7.3.8.2 Charging Status Indicator (STAT1, STAT2 Pins)
        3. 7.3.8.3 Interrupt to Host (INT)
      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 BQ25820 Registers
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Typical Application
        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 Charge Voltage Selection
          3. 8.2.1.2.3 Switching Frequency Selection
          4. 8.2.1.2.4 Inductor Selection
          5. 8.2.1.2.5 Input (VAC / SYS) Capacitor
          6. 8.2.1.2.6 Output (VBAT) Capacitor
          7. 8.2.1.2.7 Sense Resistor (RAC_SNS and RBAT_SNS) and Current Programming
          8. 8.2.1.2.8 Power MOSFETs Selection
          9. 8.2.1.2.9 ACFETs and BATFETs Selection
        3. 8.2.1.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Third-Party Products Disclaimer
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

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

8.2.1.3 Application Curves

CVAC = 160µF, COUT = 160µF

BQ25820 VAC Plug-In Power Up with 5A ICHG
VAC = 20V VBAT = 20V ICHG = 5A
Figure 8-3 VAC Plug-In Power Up with 5A ICHG
BQ25820 Charge Enable via I2C with 5A ICHG
VAC = 20V VBAT = 24V ICHG = 5A
Figure 8-5 Charge Enable via I2C with 5A ICHG
BQ25820 Charge Enable via CE Pin with 5A ICHG
VAC = 20V VBAT = 24V ICHG = 5A
Figure 8-7 Charge Enable via CE Pin with 5A ICHG
BQ25820 Buck Switching Waveform
VAC = 24V VBAT = 20V ICHG = 5A
Figure 8-9 Buck Switching Waveform
BQ25820 Buck-Boost Switching Waveform
VAC = 24V VBAT = 24V ICHG = 5A
Figure 8-11 Buck-Boost Switching Waveform
BQ25820 Reverse Mode Power Up with 4A Load
VBAT = 24V VAC_REV = 20V ILOAD = 4A
Figure 8-13 Reverse Mode Power Up with 4A Load
BQ25820 Reverse Mode Buck Transient Response
VBAT = 28V VAC_REV = 5V ILOAD = 0.5A → 4.5A
Figure 8-15 Reverse Mode Buck Transient Response
BQ25820 Reverse Mode Boost Transient Response
VBAT = 28V VAC_REV = 48V ILOAD = 0.5A → 4.5A
Figure 8-17 Reverse Mode Boost Transient Response
BQ25820 VAC Un-plug Power Down with 5A ICHG
VAC = 20V → 0V VBAT = 20V ICHG = 5A
Figure 8-4 VAC Un-plug Power Down with 5A ICHG
BQ25820 Charge Disable via I2C with 5A ICHG
VAC = 20V VBAT = 24V ICHG = 5A
Figure 8-6 Charge Disable via I2C with 5A ICHG
BQ25820 Charge Disable via CE Pin with 5A ICHG
VAC = 20V VBAT = 24V ICHG = 5A
Figure 8-8 Charge Disable via CE Pin with 5A ICHG
BQ25820 Boost Switching Waveform
VAC = 24V VOUT = 28V ICHG = 5A
Figure 8-10 Boost Switching Waveform
BQ25820 Max Power Point Tracking (MPPT) Full Panel Sweep
VOC = 30V
ISC = 3.5A		 VBAT = 24V EN_CHG = 0→ 1
Figure 8-12 Max Power Point Tracking (MPPT) Full Panel Sweep
BQ25820 Reverse Mode Power Down with 4A Load
VBAT = 24V VAC_REV = 20V ILOAD = 4A
Figure 8-14 Reverse Mode Power Down with 4A Load
BQ25820 Reverse Mode Buck-Boost Transient Response
VBAT = 28V VAC_REV = 28V ILOAD = 0.5A → 4.5A
Figure 8-16 Reverse Mode Buck-Boost Transient Response