The CJMCU-25504 is the first new intelligent integrated energy harvesting nanopower management solution ideal for ultra low power applications with special needs. The device is designed to collect and manage microwatt (μW) to milliwatt (mW) power generated from various DC sources such as photovoltaic (solar) generators or thermoelectric generators. The bq25504 is the first in its class to implement a high efficiency boost converter/charger for products and systems with tight power and operational requirements, such as Wireless Sensor Networks (WSN). The design of the bq25504 begins with a DC-DC boost converter/charger that requires only microwatts of power to start working.
  After the boost converter/charger is activated, it can efficiently extract energy from a low-voltage output collector such as a thermoelectric generator (TEG) or one/two solar panels. The boost converter can be started with VIN as low as 330mV, and after startup, it can continue to acquire energy with VIN as low as 80mV.
  The bq25504 also implements a programmable maximum power point tracking sampling network to optimize power transfer to the device. VIN_DC open-circuit voltage sampling is programmed by an external resistor and held by an external capacitor (CREF).
Characteristic

  •  Ultra Low Power, High Efficiency DC-DC Boost Converter/Charger

  •  Continuous energy harvesting from low voltage input supply: VIN ≥ 80mV (typical)

  •  Ultra-low quiescent current: IQ < 330nA (typical)

  • Cold start voltage: VIN ≥ 330mV (typical)

  •  Programmable Dynamic Maximum Power Point Tracking (MPPT)

Parameter

  •   Energy source input voltage VIN(DC): 0.13V-3V

  •   Energy storage component BAT voltage: 2.5V-5.25V

  •   Working environment temperature: -40~85 degree

  •   Boost mode switching frequency: up to 1MHZ

  •   Working mode: cold start mode, boost mode, thermal protection cut-off mode

R-DIV: Chip VRDIV pin, quickly out after dividing VIN;
BAT-OK: chip VBAT. OK, digital output, battery normal flag;
BAT: chip VBAT pin, connected to a rechargeable energy storage component such as rechargeable battery;
STOR: chip VSTOR pin, chip boost function output pin, connected to a load;
VIN: chip VIN DC pin, voltage input, connected to the collected energy source;
OCS: CPUS SAMPL pin, chip internal maximum power tracking point (MPPT) round the sampling current input pin, sampling maximum power tracking point threshold voltage is obtained by external resistance to VIN_DC voltage division; when not using maximum power tracking point circuit When the OCS pin is connected to the STOR pin;
REFS: Chip VREF SAMPL pin, the reference voltage of the maximum power tracking point (MPPT) circuit; when the                maximum power tracking point circuit is not used, the REFS pin is externally connected to a voltage or GND.
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