Single End Input - Epson S1C05251 Technical Manual

3 FUNCTIONAL DESCRIPTION

3.3.2 Single End Input

When the amp is used as single end input, two external resistors are required.
HYBRID
The gain in the input amp can be set depending on values R
To set the FSK and CAS tone signal-detection levels at node B, determine each resistance value with respect to V
as shown below.
V is the power supply voltage fed to the V
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Tables 3.3.3 and 3.3.4 show typical resistance values and amp gain for the case where V
respectively.
Parameter
R
7
R
8
Input amp gain (Typ.)
CAS - CD ON level (Typ.)
Parameter
R
7
R
8
Input amp gain
CAS - CD ON level (Typ.)
14
CASFB
R
8
CASIN
R
7
B
Figure 3.3.2 Input amp circuit
G =
AMP
R V
8
G = =
AMP
R 5
7
pin of the S1C05251.
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Table 3.3.3 Resistance values and gain (V
Value
Bellcore
1000 kΩ
562 kΩ
-5.0 dB
-35.9 dBm
Table 3.3.4 Resistance values and gain (V
Value
Bellcore
1000 kΩ
338 kΩ
-9.4 dB
-35.9 dBm
EPSON
–
Amp To filter
+
and R as shown below.
7 8
R
8
[t imes]
R
7
D D
× 0.562 [t imes]
= 5 V)
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BT
1000 kΩ
562 kΩ
-5.0 dB
-44.1 dBV
= 3 V)
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BT
1000 kΩ
338 kΩ
-9.4dB
-44.1 dBV
= 5 V and V = 3 V,
DD DD
Condition
1%
1%
Tone filter gain = -4 dB
Condition
1%
1%
Tone filter gain = -4 dB
S1C05251 TECHNICAL MANUAL
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