Other Parts Discussed in Thread: BQ25792, BQ40Z50
Hi, Team
My customer use BQ40Z50-R2 in their project. Now they needs to use Shutdown mode when ship to their end customer.
In order to wake up from the Shutdown mode, i know they have to apply a voltage greater than Vstartup to the PACK pin.
In our system, they use BQ25792+BQ40Z50-R2.
Now customer can enter Shutdown mode, but can't recover from ship mode when apply the DC input to BQ25792.
Customer prefer to check what's the Pack+ sink current value when apply a voltage to the PACK pin.
Now we suspect the sink current is too high, so when we apply the DC input to BQ25792, the BQ25792 100mA trickle can't trigger the recover.
The test is as below:
1,Remove DC input of the BQ25792.--Success.
2, send command to BQ40Z50-R2 to enter Shutdown mode. --Success.
3, apply DC input to BQ25792, we found that the BQ25792 output is 2V, the 2V BQ25792 output connect to BQ40Z50 Pack+. and BQ40Z50 will not recover from Shutdown mode.
-----BQ40Z50 not recover from Shutdown mode since 2V is <Charger Present Threshold(3V).
4, But when we remove the BQ40Z50 battery pack from BQ52792, and apply DC input to BQ25792,BQ25792 can have 5V output. we suspect the BQ40Z50 sink current is too high, that will pull the 5V output down to 2V, so that will not recover.
Pls help to give some comments.
Thanks.
G.W
