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EM8504- PMU & DC Energy Harvesting Controller

Power-Management Controller with Energy Harvester Interface for DSCC single/dual solar cell

Applications

• Energy harvesting equipped platforms
• Solar charging
• Wearable systems
• Beacons and wireless sensor networks
• Industrial and environmental monitoring
• Battery operated platforms

General Description

The EM8504 is an integrated power management solution for low power applications. It is specifically designed for efficient operation with Dye-Sensitized Solar Cells (DSSC) in the µW to mW range. 
To optimize harvesting efficiency, the EM8504 incorporates a maximum power point tracking (MPPT) controller based on a fixed Voltage at Maximum Power Point (VMPP).
The EM8504 is capable of operating with a variety of elements as secondary energy storage, namely re-chargeable batteries, super-capacitors or conventional capacitors.
Using a non-rechargeable primary battery, the EM8504’s on chip PMU offers a mechanism to extend battery life when assisted by a harvesting element. 
To perform granular power management of multiple application components, the EM8504 provides four independent supply outputs: one power supply (VSUP) and three auxiliary supplies (VAUX).
The EM8504 is delivered in a standard QFN24 package.

Main Features

• Smart Power Management
  • Ultra-low quiescent current regulator (25nA)
  • 3 auxiliary supplies with high current drive capability
  • Programmable battery output voltage level up to 4.2V
• Ultra-low input voltage and power
  • Cold-start: 0.3V / 3µW
  • Operating:  0.1V / 1µW 
• Ultra-low power solution
  • 15 nA in battery protection mode
  • 125 nA when supplying low power applications 
• Fast cold-start
  • Fast start-up using dual storage elements
  • Short Term Storage (STS)  and Long-Term Storage (LTS)
  • Maintain STS in configurable voltage window when LTS is lower than minimum application voltage
• MPPT
  • Fully embedded Maximum Power Point Tracking (MPPT), optimized for DSSC with fixed Voltage at Maximum Power Point (VMPP)
• Primary Cell Life Time Extension
  • Lifetime of non-rechargeable battery on LTS (harvester assisted)
• Flexible interface
  • SPI or I2C configuration interfaces
• Configuration stored in E2PROM
  • No external passive components required
  • Default configuration values stored in E2PROM
• Power Control
  Extensive configurability of user scenarios:
  • Battery under and over voltage protection
  • Harvesting start/stop (through input pin)
  • STS and LTS voltage status registers
  • Charging start/stop as a function of harvester power