ZHCSJI9A March 2019 – June 2019 BQ25886
PRODUCTION DATA.
- 1 特性
- 2 應用
- 3 說明
- 4 修訂歷史記錄
- 5 Device Comparison Table
- 6 Pin Configuration and Functions
- 7 Specifications
-
8 Detailed Description
- 8.1 Overview
- 8.2 Functional Block Diagram
- 8.3
Feature Description
- 8.3.1 Device Power-On-Reset
- 8.3.2 Device Power Up from Battery without Input Source
- 8.3.3 Device Power Up from Input Source
- 8.3.4 Input Current Optimizer (ICO)
- 8.3.5 Buck Mode Operation from Battery (OTG)
- 8.3.6 PowerPath Management
- 8.3.7 Battery Charging Management
- 8.3.8 Status Outputs
- 8.3.9 Input Current Limit on ILIM Pin
- 8.3.10 Voltage and Current Monitoring
- 8.3.11 Thermal Regulation and Thermal Shutdown
- 8.3.12 Battery Protection
- 8.4 Device Functional Modes
- 9 Application and Implementation
- 10Power Supply Recommendations
- 11Layout
- 12器件和文檔支持
- 13機械、封裝和可訂購信息
9.2.2.1 Inductor Selection
The device has 1.5-MHz switching frequency to allow the use of small inductor and capacitor values. The inductor saturation current should be higher than the input current (IIN) plus half the ripple current (IRIPPLE):
Equation 5. 
The inductor ripple current (IRIPPLE) depends on input voltage (VVBUS), duty cycle (D = VBAT/VBUS), switching frequency (fSW) and inductance (L):
Equation 6. 
The maximum inductor ripple current happens in the vicinity of D = 0.5. Usually inductor ripple is designed in the range of (20 – 40%) maximum charging current as a trade-off between inductor size and efficiency for a practical design.