SLUAAR7 March   2024 BQ25731 , BQ25798

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Comparison Of Charging Dock And Onboard Charging Designs
  6. 3Key Design Considerations Of Battery Charging Designs
    1. 3.1 Selection of Charger IC Topology
    2. 3.2 Selection of Charger IC Controller vs. Integrated Designs
  7. 4Battery Charger Features That Simplify Vacuum Robot Charging Design
    1. 4.1 Detection and Protection of Abnormal Charging and Operation
    2. 4.2 Safe Charging With JEITA Temperature Profile for Long Battery Lifetime
    3. 4.3 Low Power Consumption for Service Time and Long Shelf Time
  8. 5Summary
  9. 6References

5 Summary

Vacuum robots are becoming popular thanks to the robots extensive automatic features and the effectiveness of floor cleaning. Table 5-1 compares the key parameters of different designs in the application note for the applications [2][3][4]. Battery charging management and the design play very important roles in building the brand name. The onboard charger designs provide designed for designs for the maximum use of battery capacity without sacrificing the battery lifetime. The designs also achieve high power density with a good tradeoff of the total BOM cost. The protection features, JEITA temperature profile, and low quiescent current simplify the design and help achieve long service time and the ultimate goal of better customer experience.

Table 5-1 Comparison of the Chargers for Vacuum Robotics
BQ25725A BQ25730 BQ25798
Topology Buck Buck-boost Buck-boost
Switching frequency (KHz) 615, 750, 885 400, 800 750, 1500
Battery configuration 1S-4S 1S-5S 1S-4S
External FETs required 2 (SW) + 1 (PP)(1) + 1 (RBFET) 4 0
VBAT charging accuracy ± 0.5% ± 0.5% –0.65% to 0.55%
Thermistor No No JEITA
ADC No 8-bit 16-bit
Ship mode and Iq No No Yes, 11uA
Package (mm x mm) 3.5x3.5 QFN 4x4 QFN 4x4 QFN
(1) SW = switching, PP = power path