Hello,
I am using a STNS01 in my circuit for the power management. The problem is when I only have a charged battery (4.1 v) connected to the BAT pin, it does not switch to the battery voltage. As if the chip is in shutdown mode (I do not know why, the SD pin is internally pulled down and I do not activate it). To release the shutdown mode, I need to connect the IN pin to the USB and when I unplug the USB again, this time it switches to the battery (I think releasing from shutdown).
Can anybody let me know why it does not switch to the battery initially? Even I pulled down the IN pin to be sure its voltage is zero compered to the BAT pin voltage (4.1 volt).However, it did not help.
I also checked the operating condition table in the datasheet. It is kind of weird for me. Because if the voltage of the battery is in the valid range (3 ~ 4.2 v) it never switches to the battery. I think the table should be modified as below.
Best,
Mehrdad
Hello alessandro,
I'm currently experiencing the same problem as Mehrdad. I wasn't sure how to interpret you message but I finally found that out in the datasheet (Figure 16 , page 16).
But what I have now is a battery whith a voltage measured at 4,1V, Vin freshly inconnected, and my Vsys at 0V. I thought I respected the exit shutdown conditions but it don't work.
Here is my schematic:
My system is designed to get power from SYS pin. Everything is fine when USB is connected so I can debug my program. The battery is charging. But when USB is disconnected, no more power on SYS pin.
Could my connection between BATMS and BAT cause that? I figured out this connection is useless today. But I don't know if it can cause problems.
Thanks,
