ak4382a AKM Semiconductor, Inc., ak4382a Datasheet - Page 19

• Manufacturer Part Number: ak4382a
• Description: 112db 192khz 24-bit 2ch Ds Dac
• Manufacturer: AKM Semiconductor, Inc.

ASAHI KASEI
1. Grounding and Power Supply Decoupling
VDD and VSS are supplied from analog supply and should be separated from system digital supply. Decoupling capacitor,
especially 0.1 F ceramic capacitor for high frequency should be placed as near to VDD as possible. The differential Voltage
between VDD and VSS pins set the analog output range.
3. Analog Outputs
The analog outputs are full-differential outputs and 0.55 x VDD Vpp (typ) centered around the internal common voltage
(about AVDD/2). The differential outputs are summed externally, V
If the summing gain is 1, the output range is 5.5Vpp (typ @VREFH=5V). The bias voltage of the external summing circuit is
supplied externally. The input data format is 2’s complement. The output voltage (V
(@24bit) and a negative full scale for 800000H (@24bit). The ideal V
The internal switched-capacitor filter and external low pass filter attenuate the noise generated by the delta-sigma modulator
beyond the audio passb and. DC offset on AOUT+/- is eliminated without AC coupling since the analog outputs are
differential. Figure 10 and 11 show the example of external op-amp circuit summing the differential outputs.
MS0071-E-02
Figure 10. External 2
Figure 11. External 2
AOUT+
AOUT-
AOUT+
AOUT-
BIAS
47u
0.1u
nd
nd
order LPF Circuit Example (using op-amp with single power supply)
order LPF Circuit Example (using op-amp with dual power supplies)
Vop
1k
1k
4.7k
4.7k
4.7k
4.7k
3300p
4.7k
3300p
4.7k
When R1=200
When R1=180
- 19 -
fc=93.2kHz, Q=0.712, g=-0.1dB at 40kHz
fc=98.2kHz, Q=0.681, g=-0.2dB at 40kHz
When R1=200
When R1=180
R1
R1
fc=93.2kHz, Q=0.712, g=-0.1dB at 40kHz
fc=98.2kHz, Q=0.681, g=-0.2dB at 40kHz
470p
AOUT
R1
R1
470p
AOUT
4.7k
=(AOUT+)-(AOUT-) between AOUT+ and AOUT-.
4.7k
+Vop
-Vop
is 0V for 000000H (@24bit).
470p
Vop
470p
AOUT
Analog
) is a positive full scale for 7FFFFF
Out
Analog
Out
[AK4382A]
2002/12