ASAHI KASEI
[AK4112A]
0.1uF
RX
75W
Coax
75W
0.47nF
Note
AK4112A
Figure 1. 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 Receiver
470
Optical
Fiber
RX
O/E
AK4112A
Figure 2. 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 AK4112A includes the TX output buffer. The output level meets combination 0.5V+/-20% using the external resistor
network. The T1 in Figure 3 is a transformer of 1:1.
R1
TX
75 cable
W
R2
DVSS
Vdd
R1
R2
3.3V 240W 150W
3.0V 220W 150W
T1
Figure 3. TX External Resistor Network
MS0020-E-00
2000/3
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AKM [ ASAHI KASEI MICROSYSTEMS ]
