Keyboard Start-Up/Shut-Down

20037925

*** = Internal signal

1.

Keyboard de-bounce delay, 32 msec typ.

2.

Delay between LDO1 reaching 95% of its output voltage and LDO2 enable, 125 µsec typical.

3.

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

4.

RST delay, 20 msec typical.

5.

IRQ is active low.

6.

Keyboard press must be greater than 32 msec.

7.

PS_HOLD timer begins upon RST going high.

8.

Maximum of 500 msec period from RST going high to PS_HOLD going high.

9.

Response time from PS_HOLD going low to RST going low.

10. Delay between RST high-low transition to LDO2 disable.

11. Delay between LDO2 disable and LDO1 disable.

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