BQ24618: Change of VREF

PAN-M

Mastermind 8375 points

Part Number: BQ24618

Hi,

Our customer said;

The VREF becomes 3.35V at CC mode and becomes 3.30V at CV mode.
Is this movement right?

Regards,
PAN-M

over 6 years ago

0 Kedar Manishankar over 6 years ago

TI__Mastermind 24075 points

Hi PAN-M,

This is incorrect behavior as the VREF measured by customer is out of VREF range specified by EC table. VREF range is tight and has a min of 3.267V and a max of 3.333V.

Can customer confirm that

VREF capacitor is present close to VREF on IC. What is value of this capacitor?
Is customer differentiating between Analog ground (AGND) and Power Ground (PGND)?
1. If yes then measure voltage between PGND and AGND during CC and CV
Has customer tried replacing IC and if so is observed VREF different

0 PAN-M over 6 years ago in reply to Kedar Manishankar

Mastermind 8375 points

Thank you Kedar.
I will confirm the situation of the customer.
PAN-M

0 Kedar Manishankar over 6 years ago in reply to PAN-M

TI__Mastermind 24075 points

Hi Pan,

Closing thread till more data is obtained.

0 PAN-M over 6 years ago in reply to Kedar Manishankar

Mastermind 8375 points

Hi,

I confirmed the situation of the customer yesterday.
I pointed it out because a layout had a problem.
It will become normal if probably it can revise VREF because it influenced a charge current and the safety timer.
I ask you a question in a different thread when I have an additional question.

Thanks,
PAN-M

0 Kedar Manishankar over 6 years ago in reply to PAN-M

TI__Mastermind 24075 points

Hi PAN-M,

Sounds good, I will close the thread for tracking purposes so it will notify me when thread is re-opened.

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BQ24618: Change of VREF