AD1892JR Analog Devices Inc, AD1892JR Datasheet - Page 16

• Manufacturer Part Number: AD1892JR
• Description: IC SAMPLE CONV W/RX 20BIT 28SOIC
• Manufacturer: Analog Devices Inc
• Type: Sample Rate Converterr

Specifications of AD1892JR

• Rohs Status: RoHS non-compliant
• Applications: Players, Recorders
• Voltage - Supply, Digital: 4.5 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 28-SOIC (7.5mm Width)
• Voltage - Supply, Analog: -

AD1892
The AD1892 includes an on-chip 10 byte Q-channel subcode
buffer that is defined in consumer mode only. MiniDisc and
Compact Disc systems use the Q-channel subcode information
to convey format, track, index and timing information. The Q-
channel is one of eight subcode channels defined (others being
P, R, S, T, U, V and W). The other subcode channels are not
supported by the AD1892. The subcode channels are formed
by accumulating user bits over a period of 1176 subframes. The
user bits from both the left channel subframe and the right
The AD1892 stores only the Q2 through Q97 user bits that
comprise the Q-channel subcode information (96 bits); the
remaining 1080 bits (1176–96) are ignored. These 96 bits of Q-
channel subcode, organized in 12 bytes, are shown below in
Figure 26.
12-BIT WORDS
= 1176 BITS
98
Q26 Q27 Q28 Q29 Q30 Q31 Q32 Q33 Q34 Q35 Q36 Q37 Q38 Q39 Q40 Q41 Q42 Q43 Q44 Q45 Q46 Q47 Q48 Q49
Q50 Q51 Q52 Q53 Q54 Q55 Q56 Q57 Q58 Q59 Q60 Q61 Q62 Q63 Q64 Q65 Q66 Q67 Q68 Q69 Q70 Q71 Q72 Q73
Q74 Q75 Q76 Q77 Q78 Q79 Q80 Q81 Q82 Q83 Q84 Q85 Q86 Q87 Q88 Q89 Q90 Q91 Q92 Q93 Q94 Q95 Q96 Q97
Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17 Q18 Q19 Q20 Q21 Q22 Q23 Q24 Q25
CTRL
ABSOLUTE FRAME
S97
S0
S1
S2
S3
S0
S1
S2
S3
DATA10
MINUTE
DATA7
DATA4
DATA1
ZERO
1
0
0
1
1
1
0
0
1
1
ONLY Q-CHANNEL IS USED FOR CD AND MD SUBCODE
Q97
Q2
Q3
Q2
Q3
0
0
0
0
2
ADRS
Figure 25. Subcode User Bit Accumulation
Figure 26. Incoming Q-Channel Subcode
R97
R2
R3
R2
R3
0
0
0
0
3
S97
S2
S3
S2
S3
0
0
0
0
4
T97
T2
T3
T2
T3
0
0
0
0
5
ABSOLUTE MINUTE
TRACK NUMBER
U97
U2
U3
U2
U3
0
0
0
0
6
SECOND
DATA9
DATA6
DATA3
–16–
V97
V2
V3
V2
V3
7
0
0
0
0
COMPUTED OVER Q2 TO Q81
channel subframe are used to construct the subcode control
information. The user bits are accumulated into 98 12-bit
words, that form a matrix of sorts. The incoming user bits fill
this matrix row by row. The first two rows (S0 and S1) consist
of all zeros and form an easily identified subcode sync word.
The P-Channel subcode bit is always “1,” except during the
subcode sync word. The Q-channel is the first valid column of
user bits, designated Q2 through Q97 in Figure 25 below.
G(x) = x
W97
W2
W3
W2
W3
16-BIT CRC WORD
8
0
0
0
0
16
9
0
0
0
0
0
0
0
0
0
+ x
12
10
0
0
0
0
0
0
0
0
0
+ x
5
+ 1
11
ABSOLUTE SECOND
0
0
0
0
0
0
0
0
0
12
FRAME
DATA5
DATA8
DATA2
0
0
0
0
0
0
0
0
0
INDEX
SUBCODE SYNC WORD
SUBCODE SYNC WORD
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