欢迎访问ic37.com |
会员登录 免费注册
发布采购

MAS3549F 参数 Datasheet PDF下载

MAS3549F图片预览
型号: MAS3549F
PDF下载: 下载PDF文件 查看货源
内容描述: MAS 35x9F MPEG 2/3层, AAC音频解码器, G.729附录编解码器 [MAS 35x9F MPEG Layer 2/3, AAC Audio Decoder, G.729 Annex A Codec]
分类和应用: 解码器编解码器
文件页数/大小: 92 页 / 1187 K
品牌: MICRONAS [ MICRONAS ]
 浏览型号MAS3549F的Datasheet PDF文件第46页浏览型号MAS3549F的Datasheet PDF文件第47页浏览型号MAS3549F的Datasheet PDF文件第48页浏览型号MAS3549F的Datasheet PDF文件第49页浏览型号MAS3549F的Datasheet PDF文件第51页浏览型号MAS3549F的Datasheet PDF文件第52页浏览型号MAS3549F的Datasheet PDF文件第53页浏览型号MAS3549F的Datasheet PDF文件第54页  
MAS 35x9F  
DATA SHEET  
2
Table 3–16: Codec control registers on I C subaddress 6C , continued  
hex  
Register  
Address  
(hex)  
Function  
Name  
Micronas Bass (MB)  
00 22  
MB Effect Strength  
MB_STR  
MB_HAR  
bit[15:8]  
00  
7F  
MB off (default)  
maximum MB  
hex  
hex  
The MB effect strength can be adjusted in 1dB steps. A value of 40 will  
yield a medium MB effect.  
hex  
00 23  
MB Harmonics  
bit[15:8]  
00  
64  
7F  
no harmonics are added (default)  
50% fundamentals + 50% harmonics  
100% harmonics  
hex  
hex  
hex  
The MB exploits the psychoacoustic phenomenon of the ‘missing fundamental  
by creating harmonics of the frequencies below the center frequency of the  
bandpass filter (MB_FC). This enables a loudspeaker to display frequencies  
that are below its cutoff frequency. The Variable MB_HAR describes the ratio  
of the harmonics towards the original signal.  
00 24  
MB Center Frequency  
MB_FC  
bit[15:8]  
2
3
20 Hz  
30 Hz  
...  
30  
300 Hz  
The MB Center Frequency defines the center frequency of the MB bandpass  
filter (see Fig. 3–5 on page 52). The center frequency should approximately  
match the cutoff frequency of the loudspeakers. For high end loudspeakers,  
this frequency is around 50 Hz, for low end speakers around 90 Hz  
00 21  
MB Shape  
MB_SHAPE  
bit[15:8]  
5...30  
corner frequency in 10-Hz steps  
(range: 50...300 Hz)  
With a second lowpass filter the steepness of the falling edge of the MB band-  
pass can be increased (see Fig. 3–5 on page 52). Choosing the corner fre-  
quency of this filter close to the center frequency of the bandpass filter  
(MB_FC) results in a narrow MB frequency range. The smaller this range, the  
harder the bass sounds. The recommended value is around 1.5 × MB_FC  
MB Switch  
MB_SWITCH  
bit[7:2]  
bit[1]  
reserved, must be set to zero  
MB switch  
MB off  
MB on  
0
1
bit [0]  
reserved,must be set to zero  
50  
June 30, 2004; 6251-505-1DS  
Micronas  
 复制成功!