TDA8295_09 Datasheet, PDF (41/83 Pages) NXP Semiconductors – Digital global standard low IF demodulator for analog TV and FM radio

NXP Semiconductors
TDA8295
Digital global standard low IF demodulator for analog TV and FM radio
[1] Depending on actual frequency of crystal or clock signal it might happen in rare cases that AFC read value
is corrupted. For channel search algorithm it is recommended to read three times the AFC register and
discard the obviously false value.
1100
−AFC × 6750
512
(kHz)
700
001aal143
300
−100
−500
−900
−1000
−600
−200
200
600
1000
f_IF − f_nom at input (kHz)
Fig 11. Typical AFC readout versus frequency deviation of picture carrier
Table 43. Calculation of frequency deviation from AFC value
Deviation from nominal AFC[7] AFC[6] AFC[5] AFC[4] AFC[3] AFC[2] AFC[1] AFC[0]
IF frequency^[1]
f_IF = f_nom − 1674.3 kHz 0
1
1
1
1
1
1
1
f_IF = f_nom − 1661.1 kHz 0
1
1
1
1
1
1
0
:
:
:
:
:
:
:
:
:
f_IF = f_nom − 830.6 kHz
0
0
1
1
1
1
1
1
f_IF = f_nom − 817.4 kHz
0
0
1
1
1
1
1
0
:
:
:
:
:
:
:
:
:
f_IF = f_nom − 13.2 kHz
0
0
0
0
0
0
0
1
f_IF = f_nom
0
0
0
0
0
0
0
0
f_IF = f_nom + 13.2 kHz
1
1
1
1
1
1
1
1
:
:
:
:
:
:
:
:
:
f_IF = f_nom + 830.6 kHz
1
1
0
0
0
0
0
1
f_IF = f_nom + 843.8 kHz
1
1
0
0
0
0
0
0
:
:
:
:
:
:
:
:
:
f_IF = f_nom + 1674.3 kHz 1
0
0
0
0
0
0
1
f_IF = f_nom + 1687.5 kHz 1
0
0
0
0
0
0
0
[1] See Section 12 for nominal IF frequencies.
TDA8295_C2_2
Product data sheet
Rev. 02 — 27 November 2009
© NXP B.V. 2009. All rights reserved.
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