• State TI Thinks Resolved
  • Locked Locked
  • Replies 7 replies
  • Answers 1 answer
  • Subscribers 67 subscribers
  • Views 875 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.

Product recommendation

Saimon
Prodigy 640 points
Other Parts Discussed in Thread: TPS65217, TPS65721

My customer is developing a handheld project, with the following requirements.

  • Single cell Lithium Battery 3,7 V 600 mA
  • Input voltage while charging is 5 V DC
  • It should be possible to operate the device while charging: Power Path?
  • With an output voltage range between 3,7 V and 4,2 V: battery current of 250 mA when active, when inactive < 1 mA
  • Response for a 2 A current drain for 0,5 ms: within 5 ms
  • Output disable should be possible
  • Additional output if possible with 1,8 V or 3,3 V 50 mA

Please recommend the best part, and how it fits the requirements.

Thank you,

Simon

  • 0
    TI__Genius 13850 points
    Hi Saimon,

    I have assigned this thread to the application expert.

    Best regards,
    Jari Niemelä
  • 0
    TI__Mastermind 30280 points

    Simon,

    Can you provide a block diagram showing all the Ins and Outs of your power requirements? The last bullet point says

    • Additional output if possible with 1,8 V or 3,3 V 50 mA

    Other than battery charging, your application only requires 2 rails at 50mA each (1.8V and 3.3V)?

    And can you describe these bullet points in a little more detail?

    • Response for a 2 A current drain for 0,5 ms: within 5 ms
    • Output disable should be possible

    Given the available information, it looks like the TPS65217 is the best fit. If you provide more details, maybe I can find a better fit.

  • 0 in reply to Brian Berner
    TI__Genius 10885 points
    The TPS65721 sounds like a very close fit, but I'm not sure about the 2A transient requirement.
  • 0 in reply to Richard Solarski
    TI__Prodigy 640 points
    Thank you Richard & Brian.
    We´ll look into it and let you know if it fits.

    BR,
    Simon
  • 0 in reply to Saimon
    TI__Mastermind 30280 points
    Saimon,

    FYI, the TPS65217 and TPS65721 are different parts with very similar part #s :-)

    They both have battery charging and power path management, so please review and tell us which part is closer to meeting your requirements.
  • 0 in reply to Brian Berner
    Prodigy 110 points

    Thank you Brian.

    The TPS65217 will fit better, because of the power path which could deliver 2 A.

    Is there a similar device, but with only 1 DCDC and 1 LDO and without the LED driver, we don't need.

    For clarifying, the second output is 3,3 V 50 mA for GPIO which could switched off during sleep mode.

    And the third output is 1,8 V for µC and backup. In active mode 4 mA and in sleep mode <1 mA.

    The device will sleep for 15 min and peridically awake in active mode for 30 sec. In this mode the discharge current of the LiPo is 250 mA with 2 A pulses.

    Best regards,

    Matthias

  • 0 in reply to Matthias Zeilinger
    TI__Genius 9380 points
    Matthias,
    The TPS6572x part would be a good fit, but you would need a super cap on the SYS pin. SYS can only deliver 400mA so the super cap would deliver the balance of the current for the 5mS duration. A 100mF 5.5V super cap would hold the SYS pin to within 100mV during the 5mS. in reel qty the super cap would cost <$1.00. It's worth looking at.
    How often do they require the 5mS current pulse? If it's more often than 50mS then the super cap may not be the right option. You have to allow time to recharge the super cap.