• State TI Thinks Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 1 answer
  • Subscribers 64 subscribers
  • Views 448 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.

BQ24253: Battery Charger

Shlomi Yehezkia
Mastermind 6150 points
Part Number: BQ24253
Other Parts Discussed in Thread: BQ24251EVM-150, BQ24250C

Hi Team,

I would like to evaluate charger + fuel gauge from TI.

In my application I looking for charger with D+/D- so I found BQ24253.

I found that TI doesn't have EVM for BQ24253 only for BQ24251EVM-150, can I use it? is it same die as BQ24253? Does TI recommended this part or other part?

General question – how the D+/D- detection works? It can detect any USB from PC?

I would like to understand how D+/D- detection feature works.

Here are my questions:

  1. Who is detected between PC USB and charger? Is the PC USB asking which charger is connected or the opposite?
  2. Who decides how much current will use for the charging? Is it the PC USB based on the handshake with the device?
  3. If the power source is wall adaptor (connecting to the same USB port on the device) , which current will use for charging?

 

If there is an application note that describe the handshaking flow it will be excellent.

 

Thanks,

Shlomi

 

 

  • 0
    Mastermind 6150 points

    Hi Team,

    I forgot to add that my requirements are:

     

    • USB Battery Charger Li-ion polymer 1 cell 3.7v
    • Power path management between USB source and battery
    • Automatic source detector between USB from PC or USB connected to wall adaptor in order to select the charge current
    • USB of PC, Max 500mA charge current
    • USB connector to wall adaptor, charge current ~1A
    • Indication pin charger status

    Stand-alone / I2C (optional)

    Thanks,

    Shlomi

  • 0 in reply to Shlomi Yehezkia
    TI__Genius 10385 points

    Shlomi,

     

    I do not recommend you use this device for your project specifically because of its legacy D+/D- detection scheme. This device was originally designed with the USB BC1.2 specification and does not allow for 500 mA SDP (PC USB Port charging). Please provide your fully charged battery voltage and I'll be happy to make you a recommendation for a different charger IC.

     

    Thanks,

    Ricardo

  • 0 in reply to Ricardo
    Mastermind 6150 points

    Hi Ricardo,

    Thanks for your feedback.

    My battery is lithium polymer with nominal voltage of 3.7V and fully charged voltage of 4.2V.

    Actually I don’t need the D+/D- detection since I have found some workaround idea.

    In order to be more clear I’ll specify my requirements from Charger IC:

    1. Default 500mA when no FW is on our host MCU                                                                 || (state EN2=0, EN1=0 by pull-down resistors)
    2. MCU host will be able to change the state of 500mA to higher current charge by GPIO     || (state EN2=0, EN1=1)
    3. MCU host will be able to block the voltage input to the charger                                           || (state EN2=1, EN1=1)

     

    bq24250C is meet these requirements:

    bq24250C.docx

     

    Do you recommend to use bq24250C for those requirements?

    Thanks,

    Shlomi

     

     

     

  • 0 in reply to Shlomi Yehezkia
    TI__Genius 10385 points

    Shlomi,

    bq24250C will work for your applications as long as your host MCU will be able handle setting the EN1 and EN2 pins properly.

    Thanks,

    Ricardo