STAC9750 datasheet(52/73 Pages) IDT

52 / 73 page

STAC9750/9751

VALUE-LINE TWO-CHANNEL AC’97 CODECS

PC AUDIO

IDT™

STAC9750/9751

V 5.8 103106

VALUE-LINE TWO-CHANNEL AC’97 CODECS

6.5.25.2.

ADC Data on AC LINK

Bits D5-D4 select slots for ADC data on ACLINK.

6.5.25.3.

MuteFix Disable

Bit D6 controls the enable and disable of the MuteFix functions.

•

0 = MUTE FIX Enabled

•1 = MUTE FIX Disabled

When this bit is zero, and either channel is set to -46.5dB attenuation (1Fh), then that channel is fully

muted. When this bit is one, then operation is per AC’97 specification.

This bit is reserved in revisions prior to CC1.

6.5.25.4.

Mic Boost Select

The Mic boost value can be selected with bit D2, which in enabled by Register 0Eh, bit D6. Writing a

zero to bit D2 will provide 20dB of Mic Boost. Writing a one will provide 30dB of Mic Boost.

6.5.25.5.

Supply Override Select

The Supply Override bit, D1, allows override of the supply detect. Writing a zero disables the over-

ride on supply detect. Writing a one, overrides supply detect with bit D0. Bit D0 provides the supply

override value. A zero forces 3.3 V analog operation and one forces 5 V analog operation.

Table 36. ADC data on AC LINK

Value

Function

left slot 3, right slot 4

left slot 7, right slot 8

left slot 6, right slot 9

left slot 10, right slot 11

Table 37. Mic Boost Select

Value

Function

20dB

30dB

STAC9750 Datasheet(PDF) 52 Page - Integrated Device Technology