ak4648 AKM Semiconductor, Inc., ak4648 Datasheet - Page 69

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

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Power supply voltage for the Headphone-Amp is supplied from the HVDD pin and centered on the HVDD/2 voltage at
VBAT bit = “0”. The load resistance is 16 Ω (min.). HPG3-0 bits select the output voltage (Table 58).
When HPM bit = “1”, DAC output signal is output to HPL and HPR pins as (L+R)/2 mono signal.
When HPM3 bit = “1”, the signal selected by MICL3 and MICR3 bits (LIN3/RIN3 inputs or MIC-Amp outputs) to HPL
and HPR pins as (L+R)/2 mono signal.
<Connection with Headphone>
The AK4648 can be connected with the headphone as follows.
1. Single-ended Mode (In case of not using common buffer for Headphone-Amp)
MS0625-E-01
Headphone-Amp
Figure 51. External circuit example of HP-Amp (Single-ended Mode)
Table 58. Headphone-Amp volume setting (N/A: Not available)
VCOM Amp for
HP-Amp
HP-Amp
HP-Amp
HPG3-0 bits
FH-DH
AH
CH
BH
9H
8H
7H
6H
5H
4H
3H
2H
1H
0H
HVCM pin
HPR pin
HPL pin
- 69 -
Volume [dB]
0.22μF
0.22μF
-12dB
-15dB
-18dB
-21dB
-24dB
-27dB
-30dB
-33dB
10Ω
10Ω
+3dB
-3dB
-6dB
-9dB
N/A
0dB
C
C
R
R
(default)
Headphone
16Ω
16Ω
[AK4648]
2007/06