AK4371VN AKM [Asahi Kasei Microsystems], AK4371VN Datasheet - Page 32

• Manufacturer Part Number: AK4371VN
• Description: DAC with built-in PLL & HP-AMP
• Manufacturer: AKM [Asahi Kasei Microsystems]

< External Circuit of Headphone-Amp >
The cut-off frequency of the headphone-amp output depends on the external resistor and capacitor used. Table 23 shows
the cut off frequency and the output power for various resistor/capacitor combinations. The headphone impedance R
16Ω. Output powers are shown at AVDD = 2.4, 3.0 and 3.3V. The output voltage of the headphone-amp is 0.48 x AVDD
(Vpp) @−3dBFS.
< 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 VSS1 by 200kΩ (typ). In this setting, it is available to connect headphone-amp of AK4371 and external
single supply headphone-amp by “wired OR”.
MS0596-E-00
PMVCM
R [Ω]
6.8
16
0
x
0
1
1
Table 23. Relationship of external circuit, output power and frequency response (PMVREF bit = “0”)
C [μF]
220
100
100
100
PMHPL/R
47
47
0
0
1
1
BOOST=OFF
fc [Hz]
100
149
106
HPMTN
45
70
50
Figure 23. External Circuit Example of Headphone
HP-AMP
x
x
0
1
AK4371
Table 24. HP-Amp Mode Setting (x: Don’t care)
Figure 24. Wired OR with External HP-Amp
Another
HP-Amp
AK4371
BOOST=MIN
HPZ
fc [Hz]
HPL pin
HPR pin
0
1
x
x
17
43
28
78
19
47
R
- 32 -
Power-down & Mute
Normal Operation
Power-down
C
2.4V
Mode
Mute
21
10
5
Headphone
16Ω
Headphone
Output Power [mW]
3.0V
33
16
8
Pull-down by 200kΩ
Normal Operation
HPL/R pins
VSS1
VSS1
3.3V
40
20
10
[AK4371]
(default)
2007/04
L
is