Software detection and hardware detection

AN2865

14/17

Doc ID 15283 Rev 1

6

Software detection and hardware detection

If the battery voltage is not high enough to wake up the application controller but is higher

than 2.2 V, the STUSBCD01B can perform an automatic detection to allow the user to start

charging the battery and make its voltage reach a value which will wake up the ASIC. This

automatic detection is called hardware detection while the ASIC controlled detection is

referred to as software detection.

When the ASIC wakes up, the result of the hardware detection is available until the

STUSBCD01B is reset.

using the default method pin as described in Table 1 on page 5.

As in the software detection mode, the start of the detection process is triggered by the

detection is performed once per second in an infinite loop as shown in the simplified

flowchart in figure 9. This periodic detection is stopped only if:

– the detection result is positive;

Figure 9.

HW/SW detection flowchart

V

HIGH

Is V

SW

detection

Yes

End

No

HW

detection

High?

Yes

End

Start

1s timer

Yes

Timer expired

Or V

Yes

No

V

HIGH

Is V

SW

detection

Yes

End

No

HW

detection

High?

Yes

End

Start

1s timer

Yes

Timer expired

Or V

Yes

No