BQ24193: Charge operation problem

user6143488

Prodigy 110 points

Part Number: BQ24193
Other Parts Discussed in Thread: BQ2419XEVM

Dear Ti support

I'm Sesumi from Japan.

I have a question about charge operation.

After precharge operation, I saw an abnoromal operation, in which current reached about 1A~2A for about one minute.

I set Fast mode current 281.6mA,then I think current should not reach 1A~2A.

After that abnormal operation,I saw normal Fast mode operation.

Please refer attached file for regisgter setting,measure circuit and abnormal operation details.

Could you advise me about that abnormal operation.

best regards.bq24193_question.xlsx

over 4 years ago

0 Ning T over 4 years ago

TI__Mastermind 46591 points

Hi,

Referring to Fig13 Battery Charging Profile, please re-analyze your charger operation waveform. In the excel, it looks like you set fast charge REG02[7:2]=001110, i.e. 1408mA. Please also read REG08-REG0A which may report the system status and fault conditions if any.

Thanks,

Ning.

0 user6143488 over 4 years ago in reply to Ning T

Prodigy 110 points

Hi Ning T-san,

Thank you for your replying.

>In the excel, it looks like you set fast charge REG02[7:2]=001110, i.e. 1408mA.

I set REG02[0] = 1 (FORCE_20PCT bit), then current in Fast mode shuld be 1408mA x 0.2 = 261.8mA.

I read REG08, 09 in fast charge mode after abnormal mode as below,

REG08 = 0xA4, REG09=0x00. It looks like no problem.

regards.

0 Ning T over 4 years ago in reply to user6143488

TI__Mastermind 46591 points

Hi,

Have you tried multiple parts on multiple boards? Do they behave the same?

Thanks,

Ning.

0 user6143488 over 4 years ago in reply to Ning T

Prodigy 110 points

other_2_board.xlsxHi,

I've tried 2 other board.

They behaved the same as prvious board.

regards.

0 Ning T over 4 years ago in reply to user6143488

TI__Mastermind 46591 points

Hi,

Are you testing your own boards or the BQ24193 EVMs?

Thanks,

Ning.

0 user6143488 over 4 years ago in reply to Ning T

Prodigy 110 points

Hi,

I were testing my own boards ,which were designed based on magOH RED board.

Regards,

sesumi

0 Joel Hernandez II over 4 years ago in reply to user6143488

TI__Mastermind 25800 points

Hey sesumi,

We are not familiar with the magOH RED board. The only board design we support is the BQ2419xEVM.

For starters, the inductor value is not recommended size of 2.2uH. You are using 3.3uH. Additionally, the size of the inductor along with the output capacitance value of 47uF decreases the resonant double pole frequency of the LC output. While this may not necessarily be the reason for the behavior you are seeing, it is different from our expected EVM behavior.

I would suggest as Ning mentioned previously, ordering the BQ24190EVM or BQB24192EVM to test and compare the charger's behavior on the EVM vs on your board.

One other item I would check is whether the Watchdog timer is disabled in your tests. I saw in the Excel file that it may be set to 00. How often does the host communicate with the charger?

Regards,

Joel H

0 user6143488 over 4 years ago in reply to Joel Hernandez II

Prodigy 110 points

Hi, Joel

Thank you for your replying.

I'll try what you suggested, using EVM board.

As for Watchdog, because I wanted to disable Watch dog timer, I set REG05[5:4] to 00.

Is that right?

In datasheet , REG05[4:5] has TWO different description as below.

Which is right?

P25

To keep the device in host mode, the host has to reset the watchdog timer by
writing 1 to REG01[6] before the watchdog timer expires (REG05[5:4]), or disable watchdog timer by setting
REG05[5:4] = 11.

P30

REG05[5:4] 00:disable. 11:160s

regards,

Sesumi

0 Joel Hernandez II over 4 years ago in reply to user6143488

TI__Mastermind 25800 points

Hey Sesumi,

Both are correct. Resetting the watchdog timer keeps the charger in host mode, as does disabling the timer.

Regards,

Joel H

0 user6143488 over 4 years ago in reply to Joel Hernandez II

Prodigy 110 points

Hi Joels

Thank you for your replying.

About REG05[5:4], I'm afraid that below two description are contradiction.

P25

.... or disable watchdog timer by setting REG05[5:4] = 11.

P30

REG05[5:4] 00:disable. 11:160s

Then,Can I try question in other words?

To reset watchdogtimer, should I set REG05[5:4] = 00?

best regards,

Sesumi

0 Joel Hernandez II over 4 years ago in reply to user6143488

TI__Mastermind 25800 points

Hey Sesumi,

Sorry about that. I misunderstood where the confusion was.

The correct setting to disable the watchdgo is REG05[5:4] = 00.

We will correct that type in the datasheet.

Regards,

Joel H

0 user6143488 over 4 years ago in reply to Joel Hernandez II

Prodigy 110 points

Hi Joel,

Thank you for your replying.

I got it.

Regards,

Sesumi

0 Ning T over 4 years ago in reply to user6143488

TI__Mastermind 46591 points

Sesumi,

REG05[4:5]=00 disables the watchdog timer. Page 25 has typo. We will make the correction in the next revision of d.s.

Thanks,

Ning.

Power management

Power management forum

BQ24193: Charge operation problem