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RegisterDefinitions
pcm1780,pcm1781,pcm1782
SLES132A–MARCH2005–REVISEDAPRIL2005
B15B14B13B12B11B10B9B8B7B6B5B4B3B2B1B0
REGISTER160IDX6IDX5IDX4IDX3IDX2IDX1IDX0AT17AT16AT15AT14AT13AT12AT11AT10
B15B14B13B12B11B10B9B8B7B6B5B4B3B2B1B0
REGISTER170IDX6IDX5IDX4IDX3IDX2IDX1IDX0AT27AT26AT25AT24AT23AT22AT21AT20
atx[7:0]:digitalattenuationlevelsetting
wherex=1or2,correspondingtothedacoutputv
输出
l(x=1)andv
输出
r(x=2)
defaultvalue:11111111b
atx[7:0]decimalvalueattenuationlevelsetting
DAMS=0DAMS=1
11111111b2550db,noattenuation(default)0db,noattenuation(default)
11111110b254–0.5db–1db
11111101b253–1dB–2dB
::::
10011100b156–49.5db–99db
10011011b155–50dB–100dB
10011010b154–50.5dbmute
:::
10000010b130–62.5dbmute
10000001b129–63dBMute
10000000b128MuteMute
::::
00000000b0MuteMute
eachdacchannel(v
输出
LorV
输出
r)includesadigitalattenuationfunction.theattenuationlevelcanbeset
from0dbtordb,ins-dbsteps.changesinattenuatorlevelsaremadebyincrementingordecrementingby
onestep(sdb)every8/f
S
timeinternaluntiltheprogrammedattenuatorsettingisreached.alternatively,这
attenuationlevelcanbesettoinfiniteattenuation(ormute).
r(范围)ands(步伐)are–63and0.5fordams=0and–100and1fordams=1,各自.thedamsbit
isdefinedinregister21.
theattenuationdataforeachchannelcanbesetindividually.theattenuationlevelcanbecalculatedusingthe
followingformula:
attenuationlevel(db)=s
•
(atx[7:0]
DEC
–255)
whereatx[7:0]
DEC
=0through255.foratx[7:0]
DEC
=0through128withdams=0,orforatx[7:0]
DEC
=0
through154withdams=1,theattenuationlevelissettoinfiniteattenuation(沉默的).
20
: 点此下载
