ak4141 AKM Semiconductor, Inc., ak4141 Datasheet - Page 61

• Manufacturer Part Number: ak4141
• Description: Nicam/a2/eia-j Digital Stereo Decoder
• Manufacturer: AKM Semiconductor, Inc.

DM2MD
DM2LP[1:0]
DM2F[15:0]
MS0952-E-00
Addr
Addr
47H
48H
49H
Demod 2 FM/DQPSK mode. This bit is ignored while ASD is running.
Demod 2 filter select. This word is ignored while ASD is running.
Demod 2 carrier frequency. This word is ignored while ASD is running. This value represents the frequency shift
required to bring the carrier to 0 Hz, so it typically has a negative value. A positive value shifts the carrier up.
DM2F = -Fc/Fs x 2
Fc = Nominal frequency of carrier to be demodulated (in Hz)
Fs = Input sample rate (in Hz), see the Sample Rate Register table for the input sample rate that corresponds to the
selected output sample rate. The following table represents typical values, and is not meant to be restrictive. Any
16-bit value may be used as needed.
Standard Values for Fc
DM2LP[1:0]
5.7421875MHz
6.2578125MHz
6.7421875MHz
4.724212MHz
Dem2 Carrier Freq Ctrl 1
Dem2 Carrier Freq Ctrl 0
FM/DQPSK Dem Ctrl
6.552MHz
5.85MHz
00H
01H
02H
03H
Default
Default
Register Name
Register Name
R/W
R/W
16
(in 2’s complement)
DM2MD
00H
01H
728kbit/s Root Raised Cosine 100% rolloff lowpass
728kbit/s Root Raised Cosine 40% rolloff lowpass
R/W
R/W
D7
D7
0
0
Table 50. Automatic system detection
fs=48kHz/32kHz
Table 52. Demod 2 carrier frequency
0xAEC0
0xA25C
0xBE63
0xB03F
0xA916
0xA500
Demod 2 FM/DQPSK Mode
Table 51. Demod 2 Filter
R/W
R/W
D6
D6
0
0
0
50 kHz lowpass
Demod 2 Filter
DQPSK
Reserved
- 61 -
FM
R/W
R/W
D5
D5
0
0
DM2F[15:0]
R/W
R/W
D4
DM2LP[1:0]
D4
0
0
DM2F[15:8]
DM2F[7:0]
R/W
R/W
D3
D3
fs=44.1kHz
0
0
0xA932
0xA791
0xA166
0x9CF4
0x9A14
0xB895
(default)
DM2MD
R/W
R/W
D2
D2
0
0
R/W
R/W
D1
D1
0
(default)
0
(default)
0
[AK4141]
R/W
R/W
2008/05
D0
D0
0
0