• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 64 subscribers
  • Views 84 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

BQ25185: BQ25185 Vin check

Frank LAI
Prodigy 30 points
Part Number: BQ25185

Tool/software:

Hi Team

1. Does the BQ25185 accept 12V DC input for charging?

2. Can the system voltage (SYS) be fixed at 5V output?

3. When charging is disconnected, will the system voltage maintain a 5V output?

Frank

  • 0
    TI__Expert 3885 points

    Hello Frank,

    1. Yes, the BQ25185 input voltage operating range is 3 - 18V. However, thermal dissipation at a 12V input should be considered a limiting factor for charge and load current. For example, with a 12V input and a 4V battery, the charger will dissipate 0.8W for every 100mA of current.

    2. No, the system voltage (VSYS) is regulated to 4.5V when a valid input source is present.

    3. No, when the input source is removed, VSYS will just be the the battery voltage. More details about SYS regulation can be found in section 8.3.5 of the datasheet.

    Please let me know if you have any further questions.

    Best regards,

    Alec

  • 0 in reply to Alec Lehman
    Prodigy 30 points


    In Section 7.5 "Electrical Characteristics (continued)," it states that when the battery voltage is less than 3.6V, Vsys = 3.8V. I don't quite understand this.
    Does it mean that as long as the battery voltage is greater than 3.6V, Vsys will output 4.5V?

    Frank

  • 0 in reply to Frank LAI
    TI__Expert 3885 points

    Hello Frank,

    When an input source is connected and the ILIM/VSET pin is configured for a VBATREG higher than 4.3V, the system voltage (VSYS) is regulated in battery tracking mode.

    In battery tracking mode:

    • If VBAT is less than 3.6V, VSYS is regulated to 3.8V.
    • If VBAT is greater than 3.6V, VSYS is regulated to VBAT + 225mV.

    Best regards,

    Alec