BQ24075 not charge the battery

andresbonzani

Prodigy 50 points

Other Parts Discussed in Thread: BQ24075, BQ24075T, BQ24072T

Hi, mi name is Andres Bonzani and this is my first post. I speak spanish and my english not is good.

I designed a battery charger using the IC: BQ24075

The schematic is this:

The PCB´s are there:

OK, the problem is when i put the power on mi circuit, the charge no start.

The rest of my circuit works fine.

The pin SYSOFF works fine when the power is not conected (I can drive de FET ok).

The two led´s works fine. When the power and battery are connected both are turned on. When the battery is removed CHG led is turn off.

By measuring the current flowing through the battery is 0mA.

The IC is good solder.

I´m confused

I'm doing wrong?

thanks

over 13 years ago

0 Wang5577 over 13 years ago

TI__Guru 56650 points

Would you measure each pin voltage and post here? Also, please verify the part number is bq24075. Not bq24075T.

Thanks,

0 andresbonzani over 13 years ago in reply to Wang5577

Prodigy 50 points

VBAT: 3.693V

VIN: 5.989V

VOUT: 5.518V

SYSOFF: GND

The part number is bq24075TRGTR (OEC)

Thanks

0 andresbonzani over 13 years ago in reply to andresbonzani

Prodigy 50 points

Wang, can you help me plz!

Thanks

0 Wang5577 over 13 years ago in reply to andresbonzani

TI__Guru 56650 points

The part number is bq24075T. It is not bq24075. So, TS pin setup is different. Please measure the TS pin voltage.

FYI:

0 Robert Ryan over 13 years ago in reply to Wang5577

Prodigy 30 points

I could not get my bq24072T based charger to charge the battery either. I was not using a temp sensor and had a 200k and 50k voltage divider connected to the TS pin per the datasheet (pg 25). What I saw was that when VIN was in the valid range, say 6V, there was 2.6V at TS instead of the expected 1.2V. If I raised the input voltage above VOVP, the divider output was correct. Ended up with just a pulldown on TS, as shown in the eval board schematic.

Robert

0 pranavp over 13 years ago in reply to andresbonzani

Prodigy 140 points

Hi Andr��s did you got it working? i am also working with the same chip. as advised by Wang i tried the voltage divider on TS pin but for some reason it didn't worked. please let me know how you solved the problem. thanks

0 andresbonzani over 13 years ago in reply to pranavp

Prodigy 50 points

Hi Pranav, I decided to change the chip.

Buy BQ24074RGTT and works well.

Moreover, with 200 pieces I missed any

Sorry for not solving your problem. Also I will try to do some tests to use the previous chip.

regards

0 pranavp over 13 years ago in reply to andresbonzani

Prodigy 140 points

Hi Andr��s,

Thanks for the information.

Yes, i think i'll have to go with BQ24074RGTT, just wanted a small information about BQ24074RGTT, are you able to use TS pin directly without any voltage divider circuit?

also what is the voltage at TS pin?

Thanks & Regards

Pranav Pareek

0 andresbonzani over 13 years ago in reply to pranavp

Prodigy 50 points

Hello Pranav, exactly as you say, connect the battery TS pin directly to the charger TS pin.

Vin: 5v

Vout: 4.4v

VTS: 0.7v

I leave a picture of my circuit ...

0 pranavp over 13 years ago in reply to andresbonzani

Prodigy 140 points

Thanks Andres thanks a lot.

Power management

Power management forum

BQ24075 not charge the battery