VEXT Detect Start-Up/Shut Down

20037927

*** = Internal signal

1.

VEXT goes active low.

2.

VEXT 32 msec de-bounce period.

3.

Delay between LDO1 and LDO2 enables.

4.

Both LDO1 and LDO2 outputs reach 95% of respective output voltage, start Reset timer.

5.

Reset delay.

6.

Period between Reset and PS_HOLD going high is not relevant since VEXT is low

7.

PS_HOLD goes low but LDOs continue to run since VEXT is low.

8.

PS_HOLD is low and VEXT goes high, RST pin goes low.

9.

Delay between RST going low and LDO2 disabled.

10. Delay between LDO2 and LDO1 disabled.

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