la7975 Sanyo Semiconductor Corporation, la7975 Datasheet - Page 5

• Manufacturer Part Number: la7975
• Description: Pal Multi-system Sif Converter
• Manufacturer: Sanyo Semiconductor Corporation

Reference Characteristic Diagram
Input/output characteristic
Output level
Output level
Input level – dB/µV
Figure 9
Unit (resistance:
* S1 on for 6 MHz
Unit (resistance:
measurement
, capacitance: F)
D/U
ratio
Figure 10 (5.5 MHz input)
Figure 11 (6 MHz input)
Ceramic BPF
chracteristic
LA7975
)
Interference obtained with LA7975 mixer
6.552 MHz – 500 kHz = 6.052 MHz
D/U ratio
.
Pin 5 is the output pin. The output from Pin 5 is input to the
SIF via a 6 MHz bandpass filter (BPF).
When 5.5 MHz is input to Pin 1, the spectrum shown in
Figure 10 is obtained at Pin 5. Even if there is a 5.85 MHz
NICAM signal, the D/U (desirable/undesirable) ratio at Pin 5
increases and the buzz characteristic does not deteriorate.
When 6 MHz is input at Pin 1 and there is a 6.552 MHz
NICAM signal, then 6.552 MHz is mixed with 500 kHz to
make 6.052 MHz. This becomes an interference signal and is
within the band for 6 MHz. Therefore,for 6 MHz input, Pin 4
is grounded with 10 k
through the input signal 6 MHz as is.
Supply voltage, V
to stop the oscillation and pass
V
O
* Input level 80 dB/µV S1 on
– V
for 6 MHz measurement
CC
CC
– V
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