BQ25600D: COOL STATUS CARGE SAFETY TIMER ERROR.

Hi,

1. Charge termination is disabled for T1-T2 (low temp).

2. One potential workaround could be that the host gets the charge current information (e.g. via gauge) and disables charge once the charge current drops below 120mA.

Thanks,

Ning.

Hi Ning

Thanks fot your replying.

As your answer, when battery temperature T1-T2(low temp), we must obtain error detection because charge safety time.

If are there something to wrong understanding, please let me know.

Why is this specification adopted? constraint?

We want to control for low temp current setting with this IC alone.

Thanks

Hi Ning

So sorry for disturb.

We have additional question for charge IC.

Dose BQ25611D have the same specification for low temp, charge termination is disable?

Thanks

Hi,

For BQ25611D, charge termination is enabled for cool temperature.

Thanks,

Ning.

Dear Ning

Thanks for replying.
It is so useful information for me.

So sorry for disturb.
We have additional question.

When IC detecte cool temp, termination curren keep setting? or change?

For example, we set termination current 120mA for room temp.
When cool temp, termination current setteing is 120mA? or 24mA?(afeccted 0.2C)

Thanks!

Hi,

The ITERM setting should also be reduced the same as ICHG during JEITA events, but the actual Iterm might not be lower than the minimum termination current supported by the charger.

Thanks,

Ning.

Hi Ning

>The ITERM setting should also be reduced the same as ICHG during JEITA events,

Do you say, that IC is able to set Iterm for each temperature?
Or, IC change Iterm current setting automatically with temp situation?

>but the actual Iterm might not be lower than the minimum termination current supported by the charger.

Do you say, cool status termination current is set over supported minimum termination current "60mA"?

Thanks

Hi,

Will get back to you.

Thanks,

Ning.

Hi Ning

Thanks for your replying.

OK! We wait for your message.

Thanks

Hi,

In another word, when ICHG setting is reduced at cool temperature, the ITERM setting should also be reduced in the same way.

Thanks,

Ning.

Dear Ning

We confirm cool temp Iterm operation with EVM.

When TS setting get normal tempareture, we confirmed termination operation at 180mA.
But when TS setting get cool temparetue, we cannot confirm temination.
We set regiter setting with the same value.

Your explanation may be wrong.
So please check again and let me know.

Thanks.

Hi,

Which device are you referring to? BQ25600D or BQ25611D?

Thanks,

Ning.

Hi Ning

We are confirming BQ25611D.

You said as following,
       We can enable Iterm in low tempareture with BQ25611D.
       We cannot enable Iterm in low tempareture with BQ25600D.

We need to control Iterm in low tempareture.
So we comfirmed BQ25611D.

At first, we check BQ25611D operation in room tempareture.
We could see detecting Iterm.
Next, we check BQ25611D operation in low tempareture without any setting change.
We could not see detecting Iterm, BQ25611D keeps to charge operation.

I think resason is one of following,
        Your explanation is wrong.
        Or, BQ25611 is required fo sometihng setting.

So please confirm them again, and let me know the reason.

Thanks

Hi,

Could you please provide all the BQ25611D register readings when you think the device keeps charging without termination?

Thanks,

Ning.

Hi Ning

Thanks for your replying.

Please refer BQ25611 register as following.

======================
REG00 2F
REG01 1A
REG02 91
REG03 22
REG04 40
REG05 9E
REG06 E6
REG07 4C
REG08 C4
REG09 B3
REG0A 80
REG0B 54
REG0C 49
======================

This register value is for the following situations:
- When normal temperature is detected by external resistance, the termination current is detected.
After that, the low temperature is detected by the external resistance.
- In the low temperature detection state, we confirm that the termination current is not detected.
- As a result of continuing charging, an error is detected by the charge timer.

Thank.

Hi,

REG09=B3 (REG09[5:4])=11) indicates safety time expired, so the charger stopped charging.

Thanks,

Ning.

Hi Ning

I know your comment.

Because of not to detect Iterm when cool temp, BQ25611D cannot to stop charge.

So, finally, we see charge timer erorr .

This register is the value when ITERM is not detected and a charging error is detected.

Make sure that there are no problems other than errors.

Our question is as follows
1) Whether ITERM is enabled or disabled when low temperature is detected.
2) If ITERM is enabled, what is the value of ITERM?
Is it the same as room temperature? Is it different from room temperature? If not, what is the value?
3) If ITERM is enabled, why can't we check with EVT?
We can confirm ITERM at room temperature, but not at low temperature.

Please answer the three questions clearly.

Thanks

Hi,

We are double-checking and will get back to you.

Thanks,

Ning.

Hi Ning

OK.　

We wait for your replying.

Thanks

Hi,

Did you try REG0C=89 instead of 49? Does the charger behaves differently?

Thanks,

Ning.

Hi Ning

OK. We will confirm later. Please wait a moment.

But we need to set 20% of Ichg when low temp, because of battery specitication.

Please let me know, when temp detection is low and COOL current setting is 20% of Ichg, BQ25611D can detect Iterm , or not.

If BQ25611D cannot detect termincation current in COOL, we need to research other devices.

As former our messages, please anwer each following item.

==============================================================  

Our question is as follows
1) Whether ITERM is enabled or disabled when low temperature is detected.
2) If ITERM is enabled, what is the value of ITERM?
Is it the same as room temperature? Is it different from room temperature? If not, what is the value?
3) If ITERM is enabled, why can't we check with EVT?
We can confirm ITERM at room temperature, but not at low temperature.

Please answer the three questions clearly.

==============================================================

Dear Ning

Before I checked it once, I would like to ask you again about the termination current specifications of the BQ25611D.

We need to know the following specification.

[1] When BQ25611D detects COOL temp( T1~T2) with NTC, can BQ25611D detect termination current and finish charge operation?
     
[2] If [1] is possible, please let me know detail specification of termination current detection in COOL temp.
     Is termination detection current setting in COOL temp the same of TYP temp setting, or changed to suit specification?
     Additionally, please tell me the conditions such as register setting or hardware connection to enable termination current detection in COOL temp.

So please explain and answer the above 2 questions clearly.


<Background>
Before as you say, BQ25600D cannot detect termination current in COOL temp.
But we need to detect termination current in COOL temp.
So we changed the consideration device to BQ25611D.
Then please let me know BQ25611D COOL temp termination current detection specification.

<Our research>
We confirmed BQ25611D termination current detection in COOL with EVM.

First, we check in Typ temp.
We could find BQ25611D detecting termination current and finishing charge operation.

At second, we check in COOL temp without changing register setting and hardware connecting with A.
We couldn't find  BQ25611D detecting termination current.
So, BQ25611D keeps to changing operation and finally output error because of changing timer.


Thanks.