• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 63 subscribers
  • Views 286 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

BQ24650: Questions on BQ2461X Series

hongwei duan
Intellectual 450 points
Part Number: BQ24650
Other Parts Discussed in Thread: BQ24610

Hello, I would like to ask BQ24650, when I input VCC to 18V, the battery voltage is full of 16.8V is OK? Or the voltage difference between the VCC and the battery voltage is too small and the input voltage needs to be increased. How many improvements are generally appropriate? I checked all the chips of your company, which can charge 6 voltage, wide range of input voltage and battery voltage, and large charging current. Only your BQ2461X series meets some requirements, but when VCC is 18 V input, the battery voltage is 16.8V. When charging, when my switching power supply deviates.Then the BQ2461x series is in an abnormal state. So can this BQ24650 meet my requirements? I looked at the data and there was no pressure differential recommendation between 1.5V and 2V in it.

  • 0
    TI__Mastermind 24075 points
    Hi user4960217,
    As BQ24610 and BQ24650 are buck charger topology they require higher VIN than battery voltage to charge. If not, the charger will enter SLEEP mode and suspend charging. The hard limit for entering sleep mode is at 500mV (sensed close to IC), however the recommendation is to be higher by about 1.5 to 2V to account for DC losses in the high-side FET (Rdson), inductor (DCR), and input sense resistor (between ACP and ACN), the body diode drop of RBFET between VCC and input power supply, and battery sense resistor (between SRP and SRN). Depending on your charge current, what you think is VCC vs what is actually sensed on the IC can be different.
    BQ24650 will have the same requirements as BQ24610 to stay out of SLEEP mode, as can be seen from the Sleep comparator portion of both their Electrical Characteristics table.
    To check if in sleep mode, check status of LEDs if charge is being suspended and also VCC and SRN on an oscilloscope.