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AS3400 AS3410 AS3430 1v0

Data Sheet - D e t a i l e d D e s c r i p t i o n

8.5 SYSTEM

The system block handles the power up and power down sequencing, as well as, the mode switching.

8.5.1 Power Up/Down Conditions

The chip powers up when one of the following conditions is true:

The chip automatically shuts off if one of the following conditions arises:

8.5.2 Start-up Sequence

The start-up sequence depends on the used mode.

In stand-alone mode the sequence runs automatically, in I2C mode the sequence runs till a defined state and waits then for an I2C command.

Either the automatic sequence is started by setting the CONT_PWRUP bit in addition to the PWR_HOLD bit. If only the PWR_HOLD is set all

enable bits for headphone, microphone, etc have to be set manually.

Figure 17. Stand-Alone Mode Start-Up Sequence

Table 8. Power UP Conditions

#

Source

Description

1MODE pin

In stand-alone mode, MODE pin has to be driven high to turn on the device

2

I2C start

In I2C mode, a I2C start condition turns on the device

Table 9. Power DOWN Conditions

#

Source

Description

1MODE pin

Power down by driving MODE pin to low

2SERIF

Power down by SERIF writing 0h to register 20h bit <0>

3

Low Battery

Power down if VBAT is lower than the supervisor off-threshold

4VNEG CP OVC

Power down if VNEG is higher than the VNEG off-threshold