STA304A STMicroelectronics, STA304A Datasheet - Page 26

• Manufacturer Part Number: STA304A
• Description: IC PROCESSOR AUD DGTL DDX 44TQFP
• Manufacturer: STMicroelectronics
• Series: DDX™r
• Type: Audio Processorr

Specifications of STA304A

• Mounting Type: Surface Mount
• Package / Case: 44-TQFP, 44-VQFP
• Case: QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Applications: -
• Other names: 497-3944

STA304A
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:
GCEN:
Vol
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.
26/31
bypass
D15
D15
4
...Vol
GCEN
D14
0
D14
0
1 the DDX gain depends from D13-D9 bits plus D14 bit (CRA bit 2 and 3 are ignored)
if D15 = 1 set (1) or remove (0) the ddx output compressor
GAIN/VOLUME
means that the DDX gain depends from CRA bits 2 and 3
INPUT
D13
D13
Vol
4
D12
D12
Vol
3
GAIN
D11
D11
Vol
2
D10
D10
Vol
00000
00001
00010
01111
10000
11101
11110
11111
Vol
1
D9
Vol
D9
ATTENUATION
0
LIMITER
D8
D8
X
- - - -
- - - -
D7
D7
X
D6
+23.25
+21.75
+11.25
D6
+22.5
+1.50
+0.75
X
+12
dB
0
D5
RMS
D5
X
SATURATION
D4
D4
X
D3
D3
X
OUTPUT
D01AU1313
D2
D2
X
D1
D1
X
Phantom
D0
D0
X