Host-Controlled Synchronous Swithc-Mode Li-Ion Charger w/2A FET, 1 or 2 Cell 20-VQFN -40 to 85# BQ24113ARHLT Technical Documentation
## 1. Application Scenarios
### Typical Use Cases
The BQ24113ARHLT is a highly integrated single-cell Li-ion battery charger and system power path management device designed for space-constrained portable applications. Key use cases include:
Primary Applications:
- Smartphones and Tablets : Provides simultaneous battery charging and system operation from USB or adapter inputs
- Portable Medical Devices : Enables reliable power management for glucose meters, portable monitors, and diagnostic equipment
- Wearable Electronics : Compact solution for smartwatches, fitness trackers, and wireless earbuds
- IoT Devices : Powers connected sensors, smart home devices, and industrial monitoring equipment
- Portable Gaming Consoles : Manages power delivery for handheld gaming systems
Power Source Management:
- USB Charging : Supports standard USB (500mA) and charging downstream port (1.5A) configurations
- Wall Adapter Operation : Handles input currents up to 2.1A from AC-DC adapters
- Battery-Powered Operation : Maintains system operation from battery when input power is unavailable
### Industry Applications
Consumer Electronics:
- Mobile phones and smartphones requiring compact power management
- Tablets and ultra-mobile PCs needing efficient thermal performance
- Digital cameras and camcorders requiring reliable battery charging
Medical Sector:
- Portable patient monitoring systems
- Handheld diagnostic equipment
- Wearable medical sensors requiring continuous operation
Industrial Applications:
- Handheld barcode scanners and inventory management devices
- Portable test and measurement equipment
- Industrial IoT sensors and data loggers
Automotive Accessories:
- Aftermarket car entertainment systems
- Portable navigation devices
- Automotive diagnostic tools
### Practical Advantages and Limitations
Advantages:
- High Integration : Combines power path management, battery charging, and system protection in a single 3mm × 3mm package
- Thermal Regulation : Automatic charge current reduction prevents overheating during high-power operation
- Fast Charging : Supports up to 2.1A charge current for rapid battery replenishment
- Power Path Management : Enables instant system operation even with deeply discharged batteries
- USB-OTG Support : Can provide 5V boost output for USB On-The-Go applications
Limitations:
- Single-Cell Only : Limited to 4.2V/4.35V Li-ion/Li-polymer batteries
- Input Voltage Range : Maximum 6.5V input voltage restricts use in some automotive applications
- Package Size : Small QFN package may require advanced PCB assembly capabilities
- Thermal Constraints : Maximum power dissipation limited by small package size
## 2. Design Considerations
### Common Design Pitfalls and Solutions
Input Capacitor Selection:
- Pitfall : Insufficient input capacitance causing voltage droop during load transients
- Solution : Use 10μF ceramic capacitor placed close to IN pin, with additional bulk capacitance if input source has high impedance
Thermal Management:
- Pitfall : Overheating during high-current charging leading to thermal shutdown
- Solution : Implement proper thermal vias, adequate copper area, and consider environmental temperature in enclosure design
Battery Detection:
- Pitfall : False battery detection due to leakage currents or PCB contamination
- Solution : Ensure clean PCB assembly, proper BAT pin capacitance (≥10μF), and correct battery detection threshold settings
Charge Termination:
- Pitfall : Premature charge termination due to battery impedance or temperature variations
- Solution : Configure termination current appropriately for battery capacity and verify termination criteria under worst-case conditions
### Compatibility Issues with Other Components
Microcontroller Interface:
- I²C Compatibility
