WM9710

Production Data

w

PD Rev 4.0 December 2003

23

WRITE BIT

FUNCTION

PR0

PCM in ADCs and input Mux Powerdown

PR1

PCM out DACs Powerdown

PR2

Analogue mixer Powerdown

(VREF still on)

PR3

Analogue mixer Powerdown (VREF off)

PR4

Digital interface (AC-link) Powerdown

(external clock off)

PR5

Internal clock disable

PR6

HP amp Powerdown

EAPD

External amplifier Powerdown

Table 12 Powerdown Control Register Function

PR0 = 1

PR1 = 1

PR2 = 1

PR4 = 1

PR0 = 0 AND

ADC = 1

DEFAULT

READY = 1

COLD RESET

WARM

RESET

PR2 = 0 AND

ANL = 1

PR1 = 0 AND

DAC = 1

ADCs OFF

PR0

DACs OFF

PR1

ANALOGUE

OFF PR2 OR

PR3

DIGITAL I/F

OFF PR4

SHUT OFF

CODA LINK

NORMAL

Figure 11 An Example of the WM9710 Powerdown/Powerup Flow

Figure 11 illustrates one example procedure to do a complete Powerdown of the WM9710. From

normal operation sequential writes to the Powerdown Register are performed to Powerdown the

WM9710 a piece at a time. After everything has been shut off (PR0 to PR3 set), a final write (of

PR4) can be executed to shut down the WM9710’s digital interface (AC-link).

The part will remain in sleep mode with all its registers holding their static values. To wake up the

WM9710, the AC’97 controller will send a pulse on the sync line issuing a warm reset. This will

restart the WM9710’s digital interface (resetting PR4 to 0). The WM9710 can also be woken up

with a cold reset. A cold reset will cause a loss of values of the registers, as a cold reset will set

them to their default states. When a section is powered back on, the Powerdown Control/Status

Register (index 26h) should be read to verify that the section is ready (i.e. stable) before

attempting any operation that requires it.

PR0 = 1

PR1 = 1

PR4 = 1

NORMAL

ADC’s OFF

PR0

DIGITAL I/F

OFF PR4

WARM RESET

PR0 = 0 AND

ADC = 1

PR1 = 0 AND

DAC = 1

SHUT OFF

CODA LINK

DACs OFF

PR1

Figure 12 The WM9710 Powerdown Flow with Analogue Still Active