bq24616 / Battery detection

S.Satoshi

Other Parts Discussed in Thread: BQ24616, BQ24616EVM

Hi,

Please let me ask about battery detection of bq24616. I know that the battery detection is initiated POR or recharge condition is detected. Then will it be also initiated when power up with CE=Low and after that CE change from Low to High?

Best Regards,

Sonoki / Japan Disty

over 9 years ago

0 Steven Bangdiwala over 9 years ago

TI__Expert 8690 points

Hi Sonoki-san,

The bq24616 goes into battery detection in that condition as well. Any condition that allows charging, it first needs to pass the battery detection test.

Regards,
Steven

0 S.Satoshi over 9 years ago in reply to Steven Bangdiwala

Guru 21685 points

Hi Steven,

I apologize for my lacked information. Now I'm talking at the case of no battery and no NTC thermistor. Actually I checked the behavior by using bq24616EVM and then the battery detection was not run after CE pin low to high.

I just want to know if this behavior is expected as design.

bq24616EVM Battery detection with no thermistor.pdf

Best Regards,

Sonoki

0 Steven Bangdiwala over 9 years ago in reply to S.Satoshi

TI__Expert 8690 points

Sonoki-san,

What is the TS pin voltage in this case? When using the EVM, If I don't connect anything to TS, I need to force TS to around 1.7V for it to work.

Measure STAT1 and STAT2 as well.

Regards,
Steven

0 S.Satoshi over 9 years ago in reply to Steven Bangdiwala

Guru 21685 points

Hi Steven,

The TS pin voltage is approx. 2.5V with default value when no NTC is connected. And then STAT1 and STAT2 are Hi-Z both powering ACPWR and enable CE pin.

bq24616EVM Battery detection with no thermistor_2.pdf

Best Regards,

Sonoki

0 Steven Bangdiwala over 9 years ago in reply to S.Satoshi

TI__Expert 8690 points

Satoshi-san,

You should have a good voltage at the TS pin in order for it to work. 2.5V at TS is above the cold threshold and will disable charging (2.5V/3.3V = 75.75%, which is higher than 0C threshold of 71.4%). Look at 8.3.18 section and thresholds at page 8 of the datasheet.

NTC is needed to make the resistor divider work with the calculated values. If trying to test without NTC, then you need to force TS to 2.0V to be in the 60.6% range.

Please check if forcing the TS voltage to 2.0V works.

Regards,
Steven

0 S.Satoshi over 9 years ago in reply to Steven Bangdiwala

Guru 21685 points

Hi Steven,

I confirmed that the battery detection was run after power-up and CE activated with NTC. And also the charging was not started when battery was connected without NTC at both Fig.3 and Fig.4 condition in my previous post.

Best Regards,
Sonoki

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bq24616 / Battery detection