ak4648 AKM Semiconductor, Inc., ak4648 Datasheet - Page 73

• Manufacturer Part Number: ak4648
• Description: Stereo Codec With Mic/hp/spk-amp
• Manufacturer: AKM Semiconductor, Inc.

<Wired OR with External Headphone-Amp>
When PMVCM=PMHPL=PMHPR bits = “0” and HPZ bit = “1”, Headphone-Amp is powered-down and HPL/R pins are
pulled-down to VSS2 by 200k Ω (typ.). In this setting, it is available to connect Headphone-Amp of the AK4648 and
external single supply Headphone-Amp by “wired OR” and the output level of external HP-Amp should be from “ -0.3V”
to “HVDD+0.3V”. In this mode, power supply current is 20 μ A(typ.). This function is not supported in Pseudo Cap-less
Mode.
MS0625-E-01
PMVCM
x
0
1
1
PMHPL/R
0
0
1
1
HP-Amp
Another
AK4648
Figure 55. Wired OR with External Headphone-Amp
HPMTN
Table 63. HP-Amp Mode Setting (x: Don’t care)
x
x
0
1
HPL pin
HPR pin
HPZ
0
1
x
x
- 73 -
Power-down & Mute
Normal Operation
Power-down
Mode
Mute
Headphone
Pull-down by 200k Ω
Normal Operation
HPL/R pins
VSS2
VSS2
[AK4648]
2007/06
(default)