• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 62 subscribers
  • Views 774 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.

BQ25600C: A couple of clarifications needed in the datasheet

Dav01
Expert 2300 points
Part Number: BQ25600C

Dear TI power-team,

Regarding BQ25600C, please help clarify the following questions:

1) When used with <= 800mAh batteries, the preference will be to have the charger disabled. Reason being that default charge current would be to high.

- Is it possible to hard-disable it by using the CE pin and then override via i2c !?

- As CE is active low (which is a bit unfortunate as we don't have any valid rails to pull it up to) what is your suggested workaround here?

2) Regarding Type-C and OVP protection, i.e. 20V and surge.

- Would the built in OVP be sufficient (even though 20V is in the absolute maximum range)?

- If not, please suggest a solution for OVP & surge protection while still allowing bidirectional power via OTG

3) As we're planning to use OTG in Type-C DRP modes, can you please supply additional block-diagrams on how this would be implemented.

- It's not clear from the datasheet  how the reverse OTG boost  -> FET & discharge during disable is working. Please helt clarify.

4) In our case, we need to limit the current to 100-150mA,

- Please propose another pin than "VBUS" (to tap the 5V boosted supply from)

Best regards

David

  • 0
    TI__Mastermind 25800 points

    Hey David,

    Sorry for the late response.

    Regarding 1) It is not possible to do this. CE and the register bit must be set in order to enable charging. If either one is off, charge is disabled. 

    Typically, /CE can be pulled high to VSYS. Alternatively, it can be pulled up to REGN. REGN will rise when an valid input is applied, before charging would even begin normally. 

    Regarding 2) the MAX rating of the charger is 22V at VBUS. What our OVP protection will do is turn off the converter and disable biasing on the charger once the OVP threshold is hit. So you should be fine. Higher surges (>22V) and fast surges (<200ns) could present some concern, but it not, I would not worry.

    Regarding 3) One thing to note is that the bq25600C is intended to be a parallel charger in use with a master charger in order to maximize charging current to distribute power losses. Are you planning on using this in a parallel configuration? Or will this be the only charger in your system? Also, could you clarify your question here about the reverse OTG boost? Are you asking how disabling the boost converter work?

    Regarding 4) the PMID pin can be used to pull current from the OTG mode. This will bypass the input current limit when OTG current is pulled from VBUS. However, you will need extra circuitry to perform current limiting.

    Regards,

    Joel H