• State TI Thinks Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 2 answers
  • Subscribers 64 subscribers
  • Views 261 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.

BQ25618: OTG Questions

Allan Fan
Expert 7090 points
Part Number: BQ25618

Hi Expert,

Customer is looking for a solution 5Vin(USB) single cell charger with 300mA charging current(taper 30mA) with OTG, Vsys output(power path), programmable interface, and OVP features.

We are considering BQ25618 but one question regarding OTG would like to clarify with you.

The product would only have one USB typeC port and it could be either supply input or OTG 5Vout.

My questions is when in boost mode, is VBUS also same as PMID voltage e.g. 5V and can we connect accessory on VBUS leaving floating on PMID?

Why I am asking is because I see the statement in DS 8.3.4 that when in boost mode, the Q1 will be off so I am not sure connecting accessory to VBUS is a right way to do.

Would you please provide comments about it? Thanks.

Regards,

Allan

  • 0
    TI__Expert 5590 points

    Hi Allan:

    In Boost mode, the output is on PMID instead of VBUS pin. This is more like power bank application vs. OTG. You are right, Q1 FET is off during Boost mode. If you connect load to PMID mode, when VBUS is plugged in and unplug, the voltage will drop to VBAT-0.7V for about 40ms when VBUS is unplugged before Boost starts up. Can this meet your requirement? 

    Regards,

    Hong

  • 0 in reply to Hong Mao
    Prodigy 10 points

    Hi, Hong

    Could you suggest us other charger, the requirements as below 

    1. 600mAh battery 1x cell

    2.Charge voltage 4.2V terminal

    3.Charge current 300mA

    4.Termination current 30mA.

    5.support JETIA

    6.support OTG

    7.Small package as possible

  • 0 in reply to Hong Mao
    TI__Expert 7090 points

    Hi Hong,

    Could you please suggest a solution to fit all customer's requirements? Cause I couldn't find a proper one to meet all the features. 

    Thanks,

    Allan

  • 0 in reply to Allan Fan
    TI__Expert 5590 points

    Hi Allan:

    Do you need OTG voltage appearing on VBUS pin in Boost mode? I cannot find proper switching charger that can do 30mA termination while having OTG on VBUS. BQ2568 can do low charge current and low termination except the Boost  voltage is on PMID instead of VBUS.  

    Regards,

    Hong