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TSC2300
SLAS372 — NOVEMBER 2002
BIT 15
BIT 14
BIT 13
BIT 12
BIT 11
BIT 10
BIT 9
BIT 8
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
MSB
LSB
BPMUL
BPVL6
BPVL5
BPVL4
BPVL3
BPVL2
BPVL1
BPVL0
BPMUR
BPVR6
BPVR5
BPVR4
BPVR3
BPVR2
BPVR1
BPVR0
Bit 15 BPMUL
Left Channel Audio Bypass Mute. This bit is used to mute the bypass path from the left channel line input (LLINEIN) to
the left channel line and headphone outputs (VOUTL and HPL). The user can set this bit to mute the bypass path while
retaining the previous gain setting in BPVL[6:0], so that the PGA returns to the previous gain setting when BPMUL is
cleared. When the BPMUL bit is set, the PGA soft-steps down to its lowest level, then the bypass path is muted. This
procedure is used to reduce any audible artifacts (pops or clicks) during the mute operation. This soft-stepping process
is reversed when the BPMUL bit is cleared (unmute).
Table 36. Left Channel Audio Bypass Mute
BPMUL
DESCRIPTION
0
Left channel audio bypass path is active.
1
Left channel audio bypass path is mute. (default)
Bits [14:8] BPVL6- BPVL0
Left Channel Audio Bypass Path Volume Control. These 7 bits control the gain setting of the left channel bypass path
volume control PGA. This volume control can be programmed from -35.5 dB to +12 dB in 0.5 dB steps. Full volume
(+12 dB) corresponds to a setting of 7Fh. Unity gain (0 dB) corresponds to 67h. Full attenuation (-35.5 dB)
corresponds to 20h. Any value lower than 20h engages the mute function described above. The default volume setting
is 0 dB.
BPVL[6:0] = 1100111 (103d) = 0 dB (default)
BPVL[6:0] = 1111111 (127d) = +12 dB (Max)
BPVL[6:0] = 0100000 (032d) = -35.5 dB (Min)
BPVL[6:0] = 0d-31d = mute
Bit 7 BPMUR
Right Channel Audio Bypass Mute. This bit is used to mute the bypass path from the right channel line input (RLINEIN)
to the right channel line and headphone outputs (VOUTR and HPR). The user can set this bit to mute the bypass path
while retaining the previous gain setting in BPVR[6:0], so that the PGA returns to the previous gain setting when
BPMUR is cleared. When the BPMUR bit is set, the PGA soft-steps down to its lowest level, then the bypass path is
muted. This procedure is used to reduce any audible artifacts (pops or clicks) during the mute operation. This
soft-stepping process is reversed when the BPMUR bit is cleared (unmute).
Table 37. Right Channel Audio Bypass Mute
BPMUR
DESCRIPTION
0
Right channel audio bypass path is active.
1
Right channel audio bypass path is mute. (default)
Bits [6:0] BPVR6- BPVR0
Right Channel Audio Bypass Path Volume Control. These 7 bits control the gain setting of the right channel bypass
path volume control PGA. This volume control can be programmed from -35.5 dB to +12 dB in 0.5-dB steps. Full
volume (+12 dB) corresponds to a setting of 7Fh. Unity gain (0 dB) corresponds to 67h. Full attenuation (-35.5 dB)
corresponds to 20h. Any value lower than 20h engages the mute function described above. The default volume setting
is 0 dB.
BPVR[6:0] = 1100111 (103d) = 0 dB (default)
BPVR[6:0] = 1111111 (127d) = +12 dB (Max)
BPVR[6:0] = 0100000 (032d) = -35.5 dB (Min)
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