BQ40Z50-R1: bq40z50-r1 Shutdown time & ship delay & SUV delay Parameter configuration questions.

jmyang

Part Number: BQ40Z50-R1

Ti experts

1.Such as the configuration of pictures, is it allowed ?

2.In this configuration (3 cells in series), does bq40z50-r1 work like this? When the cell voltage drops to 2.6v/cell, the IC enters shutdown mode after 120 seconds delay.
Then the customer is connected to the charger (pulse voltage 2 ~ 12V), and after SUV delay (60 seconds),[note:SUV_ Mode = 1], the battery can enter normal mode? can enter charging, right?

3. Can ship delay be set to 120 seconds? The reason is that the customer's machine has a large capacitance. After the FET is turned off,
the capacitor charges the battery (the time when the capacitor voltage is greater than 2V is about 70 seconds).

over 5 years ago

0 Wyatt Keller over 5 years ago

TI__Guru** 105760 points

Hello,

Shutdown mode and SUV aren't connected, if you trip the SUV the gauge will go into permanent fail mode. It won't recover automatically like this. If it enters shutdown mode it can recover normally.

The ship delay can be set to any value allowable in the DF range, if they need to extend the time this is fine.

Sincerely,

Wyatt Keller

0 jmyang over 5 years ago in reply to Wyatt Keller

Expert 1186 points

Thanks,Keller,

1. From the test results, there is a certain relationship between shutdown time and SUV delay.

SUV=1.5V，delay=60s，

shutdown voltage=2.6V，shutdown time =10s.

For example, in the log data of the attachment is used for charging with PWM voltage, the IC always enters shutdown first,
and there is no way to activate it.

If I change the shutdown time to 120 seconds, it can be activated. Everything looks ok.

Therefore, I don't know whether it is reasonable to set shutdown time to 120 seconds?

BQ40z50-R1-3S-6V-Shutdown -12V-charge-wake-test-2020-8-10.xlsx

0 Wyatt Keller over 5 years ago in reply to jmyang

TI__Guru** 105760 points

Hello,

If you have SUV_MODE = 1 then the SUV PF check only applies to when it is exiting shutdown mode to make sure the cells are safe, as stated in the TRM section 3.2.1.

It's up to your application for how long you set the shutdown time for, if your application needs a longer delay that's okay to set at 120s.

Sincerely,

Wyatt Keller

0 jmyang over 5 years ago in reply to Wyatt Keller

Expert 1186 points

Thanks,Keller.

0 Wyatt Keller over 5 years ago in reply to jmyang

TI__Guru** 105760 points

Hello,

I hope this resolved your issue, thanks!

Sincerely,

Wyatt Keller

Power management

Power management forum

BQ40Z50-R1: bq40z50-r1 Shutdown time & ship delay & SUV delay Parameter configuration questions.