Stbc03. What will happen if IN voltage less than the battery voltage?

[DZhuy]

Hello, please help me understand:

1) What will happen if IN voltage less than the battery voltage? What voltage will in SYS in this case?

2) Сan I connect SYS pin to IN? I'ts safe?

[Winfred LU]

1) shall not happen

Battery floating voltage is adjustable up to 4.45 V.

The minimum Vin will be 4.75 V when Vfloat is set to 4.45 V.

2) take your own risks

It means to skip the protections within STBC03.

[DZhuy]

Thanks for the answer. Can you please clarify one more question:

What if the battery is fully charged (4.2 V) and we supply 4.2 V or less( for example, 3.9 V) to the IN pin. In this case, what will be the voltage on the SYS pin?

[Winfred LU]

It will not work.

There is no grantee outside the range of operating input voltage : 4.45 V to 5.4 V

[Cbalt.1]

Hello,

We could use STBC3 for stand alone application. I want to charge a mini battery as below specification.  

I am planing to draw a pcb that contains USB socket and its power will  be come from 5V phone charger. May I use the STBC3  stand alone to charge this battery or should i put mcu to control charger limits. I confused. Previously I use TP4056 IC to chage higher capacity. It is the first time i am going to charge such a lower batter.  May you give some advise to me.

Best regards.