AK4544A Datasheet, PDF (30/35 Pages) Asahi Kasei Microsystems – AC97 MULTIMEDIA AUDIO CODEC WITH SRC

[ASAHI KASEI]
[AK4544A]
1. Grounding and Power Supply Decoupling
AVdd1 and AVdd2 should be connected and derived from same AVdd. And DVdd1 and DVdd2 also should be
connected and derived from same DVdd. Analog ground and digital ground should be connected together near to
where the supplies are brought onto the printed circuit board. Decoupling capacitors should be as near to the
AK4544A as possible, with the small value ceramic capacitor being the nearest.
No specific power supply sequencing is required on the AK4544A.
2. On-chip Voltage Reference
The on-chip voltage reference are output on the VRADDA, Vref pins for decoupling. A electrolytic capacitor less than
10uF in parallel with a 0.1 uF ceramic capacitor attached to these pins eliminates the effects of high frequency noise.
No load current may be drawn from VRADDA, and Vref pins. All signals, especially clocks, should be kept away from
the VRADDA, and Vref pins in order to avoid unwanted coupling into delta-sigma modulators.
3. Codec ID configuration Pin 45,46
Physical Connection
Pin46(ID1#) Pin45(ID0#)
NC
NC
NC
GND
GND
NC
GND
GND
Logic Value
ID1
ID0
0
0
0
1
1
0
1
1
Configuration
Primary
Secondary ID01
Secondary ID10
Secondary ID11
4.Analog input
Since many analog levels can be as high as 2Vrms, the circuit shown below can be used to attenuate the analog input
2Vrms to 1Vrms which is the maximum voltage allowed for all the stereo line-level inputs.
J15
LINE_IN_L
J4
LINE_IN_R
5.SEL_CMOS(48pin)
When DVDD is 3.3V for support of CMOS level, 48pin must be open.
The other hand, 48pin must be DGND as the below figure in the case of DVDD is 5.0V for TTL level
This SEL_CMOS has to be fixed before powered up the AK4544A.
6.PC_BEEP
If PC_BEEP isn’t used, this input pin should be NC(open) or connected to Analog-Ground through capacitor. In this
case, the register for PC-Beep(04h,D15) should be set to mute on”1”. (Note that the default of PC_BEEP is mute off.)
In addition, when PC_BEEP is connected through capacity to Analog-Ground, PC_BEEP is recommended to be
separated from other non-used input pins.
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2000/04