SLUAAP0 june   2023 BQ25798

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2How MPPT and VINDPM Works on Solar Battery Chargers
    1. 2.1 Buck MPPT
    2. 2.2 Boost MPPT
    3. 2.3 Buck-Boost MPPT
  6. 3Summary
  7. 4References

Summary

There are many options to choose for Solar Battery Chargers. Buck, boost, and buck-boost converter topologies are accessible as well as a wide range of charge currents. Each battery charger works fixing the MPP Voltage or by measuring the unloaded input voltage (or OCV) and regulating the input voltage at a fixed ratio of the OCV.

For detailed features and operation, see Table 3-1 for a comparison of the solar battery chargers.

Table 3-1 Feature Comparison of Solar Battery Chargers
DeviceBQ24650BQ25798BQ25504, BQ25505, BQ25570
Input Voltage (max)28 V24 V3 V (BQ25504) and 5.1 V (BQ25505 and BQ25570)
Battery Voltage (max)26 V18.8 V5.25 V (BQ25504) and 5.5 V (BQ25505 and BQ25570)
Charge Current (max)10 A5 A0.1 A
TopologyBuckBuck-BoostBoost
ChemistryLead Acid, Li-Ion/Li-Polymer, Lithium Phosphate/LiFePO4Li-Ion/Li-Polymer, Lithium Phosphate/LiFePO4Li-Ion/Li-Polymer, SuperCap
InterfaceStandalone (RC-Settable)I2CStandalone (RC-Settable)
How to Program MPPTResistor ProgrammableI2C ProgrammableResistor Programmable
Type of MPPTFixed MPP VoltageFOCVFOCV