|
AK2306LVM Datasheet, PDF (9/36 Pages) Asahi Kasei Microsystems – ISDN/VoIPターミナルアダプタ用 2チャンネル PCMコーデック LSI | |||
|
◁ |
ASAHI KASEI
æ©è½èª¬æ
[AK2306/LV]
â PCMã¤ã³ã¿ãã§ã¼ã¹
AK2306ã¯ä»¥ä¸ã®ï¼ã¤ã®PCMãã¼ã¿ã¤ã³ã¿ãã§ã¼ã¹ããµãã¼ããã¦ãã¾ãã
ã»Long Frame Sync(LF)
ã»Short Frame Sync(SF)
ã»GCI
åãã£ã³ãã«ã®PCMãã¼ã¿ã¯å¤éåããå
±éã®ç«¯å(DR,DX)ããé 次å
¥åºåããã¾ãã
ãããã®å ´åããã¼ã¿ã¯MSBãã¡ã¼ã¹ãã§å
¥åºåããã¾ããPCMãã¼ã¿ã¹ããªã¼ã ä¸ãæåã®8bitã
B1ãã£ãã«ã次ã®8bitãB2ãã£ãã«ã§ãã
âPCMã¤ã³ã¿ã¼ãã§ã¼ã¹ã®é¸æ
Long Frame/Short Frame ã¾ãã¯GCIã®ã©ã¡ããä¸æ¹ãé¸æãã¾ãã
以ä¸ãåç
§ãã¦PCMIFã¬ã¸ã¹ã¿ãè¨å®ãã¦ä¸ããã
PCMã¤ã³ã¿ãã§ã¼ã¹é¸æã¬ã¸ã¹ã¿ï¼ã¢ãã¬ã¹ï¼101 Bitï¼0ï¼
PCMIF
PCMã¤ã³ã¿ãã§ã¼ã¹
0
LF or SF
åè
LF/SFã¯FSä¿¡å·ã§èªåå¤å®ï¼æ¬¡ãã¼ã¸åç
§ï¼
1
GCI
â ã¬ã¸ã¹ã¿åæåæã¯LF/SFã¢ã¼ã(PCMIF=0)ãé¸æããã¾ãã
â LONG FRAME (LF) / SHORT FRAME (SF)
âLF/SFã®å¤å®æ¹æ³
AK2306ã¯å
¥åãããFSã®âHâæéã«ããLong Frame, Short Frameããèªåçã«å¤æãã¾ãã
FS=âHâã®æé
ãã¬ã¼ã æ§æ
BCLKã®2å¨æ以ä¸
LF
BCLKã®1å¨æ
SF
âã¤ã³ã¿ãã§ã¼ã¹ã¿ã¤ãã³ã°
åãã£ã³ãã«ã®PCMãã¼ã¿ã¯ããã¬ã¼ã åæä¿¡å·FSã«åæãã¦ã1ãã¬ã¼ã åºé(125μs)æ¯ã«ãããã8ããã
ãã¤DX,DR端åããå
¥åºåããã¾ãã1ãã¬ã¼ã åºéã«ã¯æ大64åã®ã¿ã¤ã ã¹ããã(BCLK=4.096MHzæ)ãã
ãã¾ããã¿ã¤ã ã¹ãããæ°ï¼BCLK/64kã§ããCH0,CH1ã®ã¿ã¤ã ã¹ãããã¯åæä¿¡å·FSãã決ããããä½ç½®ã§
å
¥åºåããã¾ãã
âãã¬ã¼ã åæä¿¡å·ï¼Frame Syncï¼FSï¼
8kHzã®åºæºå
¥åä¿¡å·ã§ãã1ãã¬ã¼ã (125usæ¯)ã«8ãããã®PCMãã¼ã¿ãå
¥åºåããã¾ããBCLKã¨åæãã¦ã
ããã¨ãå¿
è¦ã§ããFSã¯PLLã®å
¥åã¨ãªããããããã¨ã«å
é¨ã®åä½ã¯ããã¯ãçæããã¾ãã
MS0093-J-06
9
2012/01
|
▷ |