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AK4141 Datasheet, PDF (91/96 Pages) Asahi Kasei Microsystems – NICAM/A2/EIA-J Digital Stereo Decoder | |||
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CONFIDENTIAL
[AK4141]
Addr
93H
Register Name
NICAM Noise SCS Threshold
R/W
Default
D7 D6 D5 D4 D3 D2 D1 D0
SNST[7:0]
R/W
1111 1111
SNST[7:0]
ã¹ãã¬ãªãã£ãªã¢ãµã¼ãç¨NICAM ãã¤ãºã¹ã¬ã·ã§ã«ããã¹ãã¬ãªãã£ãªã¢ãµã¼ãæ©è½ã§NICAM ãã¤ãº
å質ã決å®ããããã«ä½¿ããã¾ãã8-bitã¹ã¬ã·ã§ã«ãã¯ä¸ä½ã« â0âãæ¡å¼µããã£ãªã¢2ã®FMå質ã®ä¸ä½
13bit (CR2Q[15:3], CR2Q[15:3])ã¨æ¯è¼ããã¾ã(Figure 30, Table 108)ã
NICAM ãã¤ãº SCSã¹ã¬ã·ã§ã«ãã8-bitã¹ã¬ã·ã§ã«ãã¯NICAMãã¤ãºã®ä¸ä½8bit (NICN[15:8])ã¨æ¯è¼ãã
ã¾ããSNSTã®å¤ã¯ä»¥ä¸ã®æ°å¼ã§å®ç¾©ããã¾ãã
SNSTh = Average Symbol Phase Error Magnitude (degrees) * 32 / 22.5 (degrees)
Average Symbol Phase
SNST
Error Magnitude (degrees)
(decimal)
0
0
7.0
10
21.1
30
(Recommended)
22.5
32
179
255
(default)
Table 109.Typical NICAM Noise ASD Threshold Values
Addr
94H
Register Name
AVC Level Threshold High
R/W
Default
D7 D6 D5 D4 D3 D2 D1 D0
AVCH[7:0]
R/W
0010 0110
Addr
95H
Register Name
AVC Level Threshold Low
R/W
Default
D7 D6 D5 D4 D3 D2 D1 D0
AVCL[7:0]
R/W
0001 1011
AVCH[7:0], AVCL[7:0]
AVCã¤ãã¼ãã«æãAVCã¯Lchã¨Rchã®å ç®ãããä¿¡å·ã¬ãã«ããããã¹ã¬ã·ã§ã«ãã®éã«ä¿ã¤ããã«åä½
ãã¾ãããã«ã¹ã±ã¼ã«ã«å¯¾ããåºåã¬ãã«[dB]ã¯ãä¸è¨å¤ã«ãªãã¾ãã
20*log10(threshold/128)
è¨å®å¤ã¯128以ä¸ã«ãã¦ä¸ããã
MS0952-J-03
- 91 -
2013/12
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