SLUSAH0C October 2011  – June 2015


  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Description (Continued)
  6. Pin Configuration and Functions
  7. Specifications
    1. 7.1Absolute Maximum Ratings
    2. 7.2Handling Ratings
    3. 7.3Recommended Operating Conditions
    4. 7.4Thermal Information
    5. 7.5Electrical Characteristics
    6. 7.6Typical Characteristics
  8. Detailed Description
    1. 8.1Overview
    2. 8.2Functional Block Diagram
    3. 8.3Feature Description
      1. 8.3.1Maximum Power Point Tracking
      2. 8.3.2Battery Undervoltage Protection
      3. 8.3.3Battery Overvoltage Protection
      4. 8.3.4Battery Voltage in Operating Range (VBAT_OK Output)
      5. 8.3.5Nano-Power Management and Efficiency
    4. 8.4Device Functional Modes
      1. 8.4.1Cold-Start Operation (VSTOR < VSTOR_CHGEN, VIN_DC > VIN(CS) and PIN > PIN(CS))
      2. 8.4.2Main Boost Charger Enabled (VSTOR > VSTOR_CHGEN, VIN_DC > VIN(DC) and EN = LOW )
      3. 8.4.3Thermal Shutdown
  9. Application and Implementation
    1. 9.1Application Information
      1. 9.1.1Storage Element Selection
      2. 9.1.2Inductor Selection
      3. 9.1.3Capacitor Selection
        1. Capacitance
        2. Capacitance
        3. Capacitance
        4. Capacitance on VSTOR or VBAT
    2. 9.2Typical Applications
      1. 9.2.1Solar Application Circuit
        1. Requirements
        2. Design Procedure
        3. Curves
      2. 9.2.2TEG Application Circuit
        1. Requirements
        2. Design Procedure
        3. Curves
      3. 9.2.3MPPT Disabled, Low Impedance Source Application Circuit
        1. Requirements
        2. Design Procedure
        3. Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1Layout Guidelines
    2. 11.2Layout Example
    3. 11.3Thermal Considerations
  12. 12Device and Documentation Support
    1. 12.1Device Support
      1. 12.1.1Third-Party Products Disclaimer
      2. 12.1.2Zip Files
    2. 12.2Documentation Support
      1. 12.2.1Related Documentation
    3. 12.3Trademarks
    4. 12.4Electrostatic Discharge Caution
    5. 12.5Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Orderable Information

1 Features

  • Ultra Low-Power With High-Efficiency DC-DC Boost Converter/Charger
    • Continuous Energy Harvesting From Low-Input Sources: VIN ≥ 80 mV (Typical)
    • Ultra-Low Quiescent Current: IQ < 330 nA (Typical)
    • Cold-Start Voltage: VIN ≥ 330 mV (Typical)
  • Programmable Dynamic Maximum Power Point Tracking (MPPT)
    • Integrated Dynamic Maximum Power Point Tracking for Optimal Energy Extraction From a Variety of Energy Generation Sources
    • Input Voltage Regulation Prevents Collapsing Input Source
  • Energy Storage
    • Energy Can be Stored to Rechargeable Li-ion Batteries, Thin-film Batteries, Super-Capacitors, or Conventional Capacitors
  • Battery Charging and Protection
    • User Programmable Undervoltage and Overvoltage Levels
    • On-Chip Temperature Sensor With Programmable Overtemperature Shutoff
  • Battery Status Output
    • Battery Good Output Pin
    • Programmable Threshold and Hysteresis
    • Warn Attached Microcontrollers of Pending Loss of Power
    • Can be Used to Enable or Disable System Loads

2 Applications

  • Energy Harvesting
  • Solar Chargers
  • Thermal Electric Generator (TEG) Harvesting
  • Wireless Sensor Networks (WSNs)
  • Industrial Monitoring
  • Environmental Monitoring
  • Bridge and Structural Health Monitoring (SHM)
  • Smart Building Controls
  • Portable and Wearable Health Devices
  • Entertainment System Remote Controls

3 Description

The bq25504 device is the first of a new family of intelligent integrated energy harvesting nano-power management solutions that are well suited for meeting the special needs of ultra low power applications. The device is specifically designed to efficiently acquire and manage the microwatts (µW) to miliwatts (mW) of power generated from a variety of DC sources like photovoltaic (solar) or thermal electric generators. The bq25504 is the first device of its kind to implement a highly efficient boost converter/charger targeted toward products and systems, such as wireless sensor networks (WSNs) which have stringent power and operational demands. The design of the bq25504 starts with a DC-DC boost converter/charger that requires only microwatts of power to begin operating.

Once started, the boost converter/charger can effectively extract power from low-voltage output harvesters such as thermoelectric generators (TEGs) or single- or dual-cell solar panels. The boost converter can be started with VIN as low as 330 mV, and once started, can continue to harvest energy down to VIN = 80 mV.

Device Information(1)

bq25504VQFN (16)3.00 mm x 3.00 mm
  1. For all available packages, see the orderable addendum at the end of the datasheet.

Solar Application Circuit

bq25504 fp_app_sch_lusah0.gif

4 Revision History

Changes from B Revision (December 2014) to C Revision

Changes from A Revision (September 2012) to B Revision

  • Added Handling Rating table, Feature Description section, Device Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information sectionGo

Changes from * Revision (October 2011) to A Revision

  • Added the INTENDED OPERATION sectionGo
  • Changed the Cold -Start Operation sectionGo
  • Changed the Boost Converter, Charger Operation sectionGo
  • Changed the Storage Element sectionGo
  • Changed the CAPACITOR SELECTION sectionGo
  • Added CFLTR and Notes 1 and 2 to Figure 14Go
  • Added CFLTR and Notes 1 and 2 to Figure 21Go
  • Added CFLTR and Notes 1 and 2 to Figure 28Go