STA304A

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12.11Phantom Center Register (add. 60h)

Setting bit 0 enables the phantom center channel feature. When this feature is on, the content of the center

channel is split and added to the L and R channels.

12.12DDX Gain Register (add. 62h)

bypass:

0

means that the DDX gain depends from CRA bits 2 and 3

1 the DDX gain depends from D13-D9 bits plus D14 bit (CRA bit 2 and 3 are ignored)

GCEN:

if D15 = 1 set (1) or remove (0) the ddx output compressor

The STA304A provides continuous digital gain and limiting functionality. Digital gain is variable from 0dB to

+23.25dB in 0.75dB steps based in the 62h register when the bit 15 is set. If the bit 15 is not set, th STA304A

defaults to the original Gain/Limiting truth table based on DDX_Gain bits (12.9). The GCEN bit when set enables

limiting to prevent clipping. This limiter uses a peak detect algoritthm for attack and a RMS detect for release.

The attack threshold is set at full DDX output power and will therefore reduce the gain when clipping is occuring.

The release threshold is set slightly below this to allow for a minimum dynamic range.

Figure 16.

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Phantom

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

bypass

GCEN

XXXXXXXX

X

Vol

dB

00000

+23.25

00001

+22.5

00010

+21.75

- - - -

01111

+12

10000

+11.25

- - - -

11101

+1.50

11110

+0.75

11111

0

LIMITER

GAIN/VOLUME

INPUT

OUTPUT

ATTENUATION

GAIN

RMS

SATURATION

D01AU1313