AK4589_1 Datasheet, PDF (49/76 Pages) Asahi Kasei Microsystems – 2/8-Channel Audio CODEC with DIR

ASAHI KASEI
Biphase signal input/output circuit
[AK4589]
75Ω
Coax
0.1uF
RX
75Ω
AK4589
Figure 23. Consumer Input Circuit (Coaxial Input)
Note: In case of coaxial input, if a coupling level to this input from the next RX input line
pattern exceeds 50mV, there is a possibility to occur an incorrect operation. In this case, it is
possible to lower the coupling level by adding this decoupling capacitor.
Optical
Fiber
Optical Receiver
O/E
470
RX
AK4589
Figure 24. Consumer Input Circuit (Optical Input)
In case of coaxial input, as the input level of RX line is small, in Serial Mode, be careful not to crosstalk among RX input
lines. For example, by inserting the shield pattern among them. In Parallel Mode, only one channel input (RX1) is
available and RX2-4 change to other pins for audio format control. Those pins must be fixed to “H” or “L”.
The AK4589 includes the TX output buffer. The output level meets combination 0.5V+/-20% using the external resistor
network. The T1 in Figure 25 is a transformer of 1:1.
330±2%
TX
DVSS
100±2%
75Ω cable
T1
Figure 25. TX External Resistor Network
MS0339-E-00
- 49 -
2004/09