M
n
n 0
H(z)
FIR z
M
24 for PRB _ R3, PRB _ R6, PRB _ R15, and PRB _ R18
M
19 for PRB _ R9 and PRB _ R12
-
=
(4)
SLAS553A – NOVEMBER 2008 – REVISED SEPTEMBER 2009...................................................................................................................................... www.ti.com
Table 8. ADC Biquad Filter Coefficients (continued)
Filter
FIlter Coefficient
ADC Coefficient, Left Channel
ADC Coefficient, Right Channel
BIQUAD C
N0
C17 (page 4 / register 34, 35)
C49 (page 4 / register 98, 99)
N1
C18 (page 4 / register 36, 37)
C50 (page 4 / register 100, 101)
N2
C19 (page 4 / register 38, 39)
C51 (page 4 / register 102, 103)
D1
C20 (page 4 / register 40, 41)
C52 (page 4 / register 104, 105)
D2
C21 (page 4 / register 42, 43)
C53 (page 4 / register 106, 107)
BIQUAD D
N0
C22 (page 4 / register 44, 45)
C54 (page 4 / register 108, 109)
N1
C23 (page 4 / register 46, 47)
C55 (page 4 / register 110, 111)
N2
C24 (page 4 / register 48, 49)
C56 (page 4 / register 112,113)
D1
C25 (page 4 / register 50, 51)
C57 (page 4 / register 114, 115)
D2
C26 (page 4 / register 52, 53)
C58 (page 4 / register 116, 117)
BIQUAD E
N0
C27 (page 4 / register 54, 55)
C59 (page 4 / register 118, 119)
N1
C28 (page 4 / register 56, 57)
C60 (page 4 / register 120, 121)
N2
C29 (page 4 / register 58, 59)
C61 (page 4 / register 122,123)
D1
C30 (page 4 / register 60, 61)
C62 (page 4 / register 124, 125)
D2
C31 (page 4 / register 62, 63)
C63 (page 4 / register 126, 127)
FIR Section
Six of the available ADC processing blocks offer FIR filters for signal processing. PRB_R9 and PRB_R12 feature
a 20-tap FIR filter, whereas the processing blocks PRB_R3, PRB_R6, PRB_R15, and PRB_R18 feature a 25-tap
FIR filter.
The coefficients of the FIR filters are 16-bit 2s-complement format and correspond to the ADC coefficient space
as listed in
Table 9. There is no default transfer function for the FIR filter. When the FIR filter is used, all
applicable coefficients must be programmed.
Table 9. ADC FIR Filter Coefficients
Filter Coefficient
ADC Coefficient, Left Channel
ADC Coefficient, Right Channel
FIR0
C7 (page 4 / register 14, page 4 / register 15)
C39 (page 4 / register 78, page 4 / register 79)
FIR1
C8 (page 4 / register 16, page 4 / register 17)
C40 (page 4 / register 80, page 4 / register 81)
FIR2
C9 (page 4 / register 18, page 4 / register 19)
C41 (page 4 / register 82, page 4 / register 83)
FIR3
C10 (page 4 / register 20, page 4 / register 21)
C42 (page 4 / register 84, page 4 / register 85)
FIR4
C11 (page 4 / register 22, page 4 / register 23)
C43 (page 4 / register 86, page 4 / register 87)
FIR5
C12 (page 4 / register 24, page 4 / register 25)
C44 (page 4 / register 88, page 4 / register 89)
FIR6
C13 (page 4 / register 26, page 4 / register 27)
C45 (page 4 / register 90, page 4 / register 91)
FIR7
C14 (page 4 / register 28, page 4 / register 29)
C46 (page 4 / register 92, page 4 / register 93)
FIR8
C15 (page 4 / register 30, page 4 / register 31)
C47 (page 4 / register 94, page 4 / register 95)
FIR9
C16 (page 4 / register 32, page 4 / register 33)
C48 (page 4 / register 96, page 4 / register 97)
FIR10
C17 (page 4 / register 34, page 4 / register 35)
C49 (page 4 / register 98, page 4 / register 99)
FIR11
C18 (page 4 / register 36, page 4 / register 37)
C50 (page 4 / register 100, page 4 / register 101)
FIR12
C19 (page 4 / register 38, page 4 / register 39)
C51 (page 4 / register 102, page 4 / register 103)
FIR13
C20 (page 4 / register 40, page 4 / register 41)
C52 (page 4 / register 104, page 4 / register 105)
FIR14
C21 (page 4 / register 42, page 4 / register 43)
C53 (page 4 / register 106, page 4 / register 107)
FIR15
C22 (page 4 / register 44, page 4 / register 45)
C54 (page 4 / register 108, page 4 / register 109)
FIR16
C23 (page 4 / register 46, page 4 / register 47)
C55 (page 4 / register 110, page 4 / register 111)
38
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