National Semiconductor LM4985, Руководство пользователя

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Appendix C Volume Control
Settings Binary Values
The minimum volume setting is set to –76dB when 00000 is
loaded into the volume control register. Incrementing the
volume control register in binary fashion increases the vol-
ume control setting, reaching full scale at 11111. Table C1
shows the value of the gain for each of the 32 binary volume
control settings.
Table C1. Binary Values for the Different Volume Control Gain Settings
Gain B4 B3 B2 B1 B0
18 1 1 1 1 1
17 1 1 1 1 0
16 1 1 1 0 1
15 1 1 1 0 0
14 1 1 0 1 1
13 1 1 0 1 0
12 1 1 0 0 1
10 1 1 0 0 0
8 1 0 1 1 1
6 1 0 1 1 0
4 1 0 1 0 1
2 1 0 1 0 0
0 1 0 0 1 1
–2 1 0 0 1 0
–4 1 0 0 0 1
–6 1 0 0 0 0
–8 0 1 1 1 1
–10 0 1 1 1 0
–12 0 1 1 0 1
–14 0 1 1 0 0
–16 0 1 0 1 1
–18 0 1 0 1 0
–21 0 1 0 0 1
–24 0 1 0 0 0
–27 0 0 1 1 1
–30 0 0 1 1 0
–34 0 0 1 0 1
–38 0 0 1 0 0
–44 0 0 0 1 1
–52 0 0 0 1 0
–62 0 0 0 0 1
–76 0 0 0 0 0
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