TI公司的BQ25504是一款最新集成納米智能能源收集電源管理解決方案，本方案非常適合有特殊需要的超低功耗的應用環境。該產品是專門設計來有效地獲取和管理微瓦和毫瓦的電力，電力通常來自各種光伏太陽能直流源或熱電動發電機。BQ25504是第一種面向產品和系統實現高效的執行轉換器或充電器，例如應用在對操作功耗有嚴格的需求無線電傳感器網絡。采用BQ25504設計的DC-DC升壓轉換器/充電器，只需要毫瓦的電力就可以工作。本文通過總結BQ25504器件的特點，介紹器件、特性、應用方向及內部結構框圖，并給參考設計實例原理圖、制板圖及元器件清單。
The bq25504 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 product 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 (WSN) which have stringent power and operational demands. The design of the bq25504 starts with a DCDC boost converter/charger that requires only microwatts of power to begin operating.
BQ25504主要特性：
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 Re-Chargeable 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/Disable System Loads
BQ25504應用：
• Energy Harvesting
• Solar Charger
• Thermal Electric Sources Generator (TEG) Harvesting
• Wireless Sensor Networks (WSN)
• Industrial Monitoring
• Environmental Monitoring
• Bridge and Structural Health Monitoring (SHM)
• Smart Building Controls
• Portable and Wearable Health Devices
• Entertainment System Remote Controls
圖1. BQ25504方框圖
BQ25504參考設計主要特性：
• Evaluation module for bq25504
• Ultra low power boost converter/charger with battery management for energy harvester applications
• Resistor-programmable settings for under voltage, over voltage providing flexible battery management;
POTs Included for fine tuning the settings (not populated)
• Programmable push-pull output Indicator for battery status (VBAT_OK)
• Test points for key signals available for testing purpose – easy probe hook-up.
• Jumpers available – easy to change settings
BQ25504設計原理圖：
圖2. BQ25504設計原理圖
BQ25504設計方案材料清單：
PCB元件布局圖：
