AK4955 Datasheet, PDF (62/117 Pages) Asahi Kasei Microsystems – 24bit Stereo CODEC with MIC/SPK/Cap-less VIDEO-AMP/ LDO & DSP

[AK4955]
■ Stereo Line Output (LOUT, ROUT pin)
When DACL bit is set to “1”, L and R channel signals of DAC are output in single-ended format via LOUT and ROUT
pins. When DACL bit is “0”, output signals are muted and LOUT and ROUT pins output common voltage. The load
impedance is 10kΩ (min.). When the PMLO bit = LOPS bit = “0”, the stereo line output enters power-down mode and the
output is pulled-down to VSS1 by 100kΩ(typ). When the LOPS bit is “1”, stereo line output enters power-save mode. Pop
noise at power-up/down can be reduced by changing PMLO bit when LOPS bit = “1”. In this case, output signal line
should be pulled-down by 20kΩ after AC coupled as Figure 49. Rise/Fall time is 300ms (max) when C=1μF and
R_L=10kΩ. When PMLO bit = “1” and LOPS bit = “0”, stereo line output is in normal operation.
LVCM1-0 bits set the gain of stereo line output.
“DACL bit” “LVCM1-0 bits”
DAC
LOUT pin
ROUT pin
Figure 48. Stereo Line Output
LOPS bit
0
1
PMLO bit
Mode
LOUT/ROUT pin
0
Power Down
Pull-down to VSS1
1
Normal Operation
Normal Operation
0
Power Save
Fall down to VSS1
1
Power Save
Rise up to
Common Voltage
Table 57. Stereo Line Output Mode Select
LVCM1-0 bits
LVDD
Gain
00
2.7 ~ 5.5 V
−1.34dB (default)
01
3.0 ~ 5.5 V
0dB
10
4.0 ~ 5.5 V
+2.50dB
11
4.5 ~ 5.5V
+3.52dB
Table 58. Stereo Lineout Volume Setting
(default)
LOUT 1μF
ROUT
220Ω
20kΩ
Figure 49. External Circuit for Stereo Line Output (in case of using a Pop Noise Reduction Circuit)
MS1343-E-00
- 62 -
2011/12