750mA SINGLE-CHIP Li-Ion/Li-Pol CHARGE MANAGEMENT IC with Thermal Regulation 10-VSON 0 to 125# BQ24087DRCT Technical Documentation
## 1. Application Scenarios
### Typical Use Cases
The BQ24087DRCT is a highly integrated single-cell Li-ion and Li-polymer battery charger IC with power path management, designed for space-constrained portable applications. Key use cases include:
Portable Medical Devices
- Wearable health monitors requiring continuous operation
- Portable diagnostic equipment with battery backup
- Medical sensors needing simultaneous charge and system operation
Consumer Electronics
- Smartphones and tablets requiring fast charging capabilities
- Wireless earbuds and hearables with compact form factors
- Portable gaming devices with extended battery life requirements
IoT and Wearable Devices
- Smartwatches and fitness trackers
- Industrial IoT sensors with battery-powered operation
- Home automation controllers requiring reliable power management
### Industry Applications
- Healthcare : Medical patches, portable diagnostic tools, patient monitoring systems
- Consumer Electronics : Mobile accessories, portable audio devices, handheld gadgets
- Industrial : Portable test equipment, data loggers, remote monitoring systems
- Automotive : Aftermarket accessories, portable navigation devices
### Practical Advantages
Key Benefits:
- Integrated Power Path Management : Enables simultaneous charging and system operation
- High Efficiency : Up to 92% efficiency with 1.5A charge current capability
- Compact Solution : 3mm × 3mm VQFN package ideal for space-constrained designs
- Safety Features : Thermal regulation, battery temperature monitoring, and safety timers
- Flexible Input Sources : Supports USB and adapter inputs with automatic detection
Limitations:
- Single-cell battery support only (no multi-cell configurations)
- Maximum input voltage of 6.5V limits high-voltage adapter compatibility
- Requires external components for complete solution (inductor, capacitors, resistors)
- Limited to 1.5A maximum charge current for high-power applications
## 2. Design Considerations
### Common Design Pitfalls and Solutions
Pitfall 1: Thermal Management Issues
- Problem : Inadequate thermal dissipation causing charger shutdown
- Solution : Implement proper thermal vias, use copper pours, and consider board stacking
Pitfall 2: Input Source Instability
- Problem : Unstable input voltage causing frequent charge termination
- Solution : Add input capacitance (10µF recommended) and implement input voltage monitoring
Pitfall 3: Battery Connection Problems
- Problem : Poor battery connection leading to inaccurate charge termination
- Solution : Ensure robust battery connector design and implement proper PCB routing
### Compatibility Issues
Input Source Compatibility:
- Works with standard USB ports (500mA/900mA) and wall adapters
- May require additional circuitry for non-standard power sources
- Compatible with USB Battery Charging Specification 1.2
Battery Compatibility:
- Optimized for single-cell Li-ion/Li-polymer batteries (3.6V-4.2V)
- Requires battery protection circuit for safe operation
- Compatible with various battery chemistries within voltage range
System Integration:
- I²C interface compatible with most microcontrollers
- Requires level translation for 1.8V systems
- Compatible with standard PMBus commands
### PCB Layout Recommendations
Power Path Routing:
- Keep input capacitor (C1) within 2mm of VIN and GND pins
- Route battery connection with wide traces (minimum 20 mil)
- Place inductor (L1) close to SW pin to minimize EMI
Thermal Management:
- Use thermal vias under the exposed thermal pad
- Connect thermal pad to large ground plane
- Maintain adequate copper area for heat dissipation
Signal Integrity:
- Route I²C signals away from switching nodes
- Keep TS (temperature sense) connection short and guarded
- Separate
