CS8420-DSZR Cirrus Logic Inc, CS8420-DSZR Datasheet - Page 79

• Manufacturer Part Number: CS8420-DSZR
• Description: IC,Digital Audio Sample Rate Converter,SOP,28PIN
• Manufacturer: Cirrus Logic Inc

DS245F4
14.2
The TXP pin may be used to drive TTL or CMOS gates as shown in
optical connectors for digital audio since they usually have TTL or CMOS compatible inputs. This circuit is
also useful when driving multiple digital audio outputs since RS422 line drivers have TTL compatible inputs.
AES3 Receiver External Components
The CS8420 AES3 receiver is designed to accept both the professional and consumer interfaces. The dig-
ital audio specifications for professional use call for a balanced receiver, using XLR connectors, with 110 Ω
±20% impedance. The XLR connector on the receiver should have female pins with a male shell. Since the
receiver has a very high input impedance, a 110 Ω resistor should be placed across the receiver terminals
to match the line impedance, as shown in
they are, however, strongly recommended.
Figures 33
This improves the robustness of the receiver, preventing the saturation of the transformer, or any DC current
flow, if a DC voltage is present on the cable.
In the configuration of systems, it is important to avoid ground loops and DC current flowing down the shield
of the cable that could result when boxes with different ground potentials are connected. Generally, it is
good practice to ground the shield to the chassis of the transmitting unit, and connect the shield through a
capacitor to chassis ground at the receiver. However, in some cases it is advantageous to have the ground
of two boxes held to the same potential, and the cable shield might be depended upon to make that electrical
If some isolation is desired without the use of transformers, a 0.01 μF capacitor should be placed in series
with each input pin (RXP and RXN) as shown in
frequency energy could be coupled into the receiver, causing degradation in analog performance.
and
34
show an optional DC blocking capacitor (0.1 μF to 0.47 μF) in series with the cable input.
Twisted
Twisted
Figure 34. Transformerless Professional Input Circuit
110 Ω
110 Ω
Pair
Pair
CS8420
Figure 33. Professional Input Circuit
XLR
XLR
TXN
TXP
Figure 32. TTL/CMOS Output Circuit
1
1
* See Text
* See Text
Figure
110 Ω
33. Although transformers are not required by the AES,
Figure
110 Ω
0.01 F
0.01 F
μ
34. However, if a transformer is not used, high
μ
TTL or
CMOS Gate
CS8420
RXP
RXN
Figure
CS8420
RXP
RXN
32. This circuit may be used for
CS8420
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