BQ25120A: BQ25120A chip specification question

user4206199

Part Number: BQ25120A

Dear All

For BQ25120A,I have some question,pls help check it

1.It not charge to battery if TS unconnected?

2.From below block diagram，we can find Device Control portion from IN Pin. whether I2C can nomal work if battery only?if yes and we want to known the power supply via Q1/Q2?

3. whether CD pin must pull up if I want to I2C nomal work?

over 7 years ago

0 Robin Tang over 7 years ago

TI__Prodigy 670 points

Hi, pls check my feedback:

1. Not recommend to float the TS pin, since it's a voltage based temperature sensing, float TS pin may cause a uncertain voltage at this pin.

2. Yes, the I2C still can work if battery only. The Q1/2 will block the battery voltage, so at VIN side you shouldn't see a voltage.

3. Yes, if CD pin is low when battery only, the device is in HiZ mode and I2C not work, you need toggle the CD pin to enable the I2C.

Thanks,

0 user4206199 over 7 years ago in reply to Robin Tang

Intellectual 470 points

Robin

Thanks for your quickly support

0 user4206199 over 7 years ago in reply to user4206199

Intellectual 470 points

Robin

I have another question ask for advice，
1.if TS pin unconnect and IN pin connect 5V，PMID pin no voltage and not charge,PMID have voltage after conncet divider resistance now.why?
2.if TS pin unconnect and disable TS function from TS control register,PMID no voltage after CD pin connect pull down and IN pin connect 5V,why?

0 Robin Tang over 7 years ago in reply to user4206199

TI__Prodigy 670 points

Hi,

1. If IN pin connect 5V, the PMID will has voltage.

2. If IN connect to 5V and pull down the CD pin, the bq25120A enable charging, PMID should has voltage, what's exact test condition that cause the PMID no voltage? pls give more detail test condition.

Thanks,

0 haiquan yuan over 7 years ago in reply to Robin Tang

Prodigy 10 points

1.if TS pin unconnect （Other configuration

The same as the reference design）， IN pin connect 5V，PMID pin no voltage ？
2.if TS pin unconnect and disable TS function from TS control register,PMID no voltage after CD pin connect pull down and IN pin connect 5V,why?

0 Robin Tang over 7 years ago in reply to haiquan yuan

TI__Prodigy 670 points

I already feedback you in previous reply. Pls check my comments.

Power management

Power management forum

BQ25120A: BQ25120A chip specification question