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

4.3 Low Power Consumption for Service Time and Long Shelf Time

The battery charger power consumption needs to be very low when not working for longer standby time. To implement such a feature, BQ25798 implemented the feature that the charger IC can be set in SHIPMODE by turning off the optional SHIP FET as shown in Figure 3-3 to achieve the lowest power consumption of 11uA. The parameter test conditions in the EC table as shown in Table 4-1 from the BQ25798 data sheet.

Table 4-1 The Quiescent Current Specification
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
IQ_BAT_OFF Quiescent battery current (BATP) for when the charger is in ship mode VBAT = 8V, No VBUS, I2C enabled, ADC disabled, in ship mode, TJ < 85 °C 11 16 µA

The vacuum robot system can be woken by pulling QON low (push the ON button) as shown in Figure 3-3. All these features are implemented by the hardware and help the system design.