TDA8295 Datasheet, PDF (41/77 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
Table 45. D_IF_AGC_STAT register (address 27h) bit description
Bit Symbol
Access Value Description
7 to 0 D_IF_AGC_STAT[7:0] R
-
D_IF_AGC_STAT is the digital IF AGC status
readout byte. Contains the digital IF AGC loop
DC information. The format is twos
complement. To get the internal gain in dB, the
following formula can be used:
gain = ^D-----^_---^I--^F---^_---^A----^G--₃--^C-_.--₆-^_--₇-^S--₅-^T----^A---^T-----⁺-----⁵---⁰-- (dB) .
Table 46. T_IF_AGC_STAT register (address 28h) bit description
Bit Symbol
Access Value Description
7 to 0 T_IF_AGC_STAT[7:0] R
-
T_IF_AGC_STAT is the IF AGC status readout
byte. Contains the tuner IF AGC loop DC
information. The format is offset binary.
9.3.14 Debug register for ADC and DAC test
Table 47. ANALOG_DEBUG register (address 2Ah) bit description
Legend: * = default value.
Bit Symbol Access Value Description
7 to 2 -
R/W -
not used
1
ADC_TEST R/W
If ADC_TEST is HIGH, the ADC input signal is interpolated
to 108 MHz and fed to video and sound DAC output; the
main circuitry is bypassed. This feature is intended mainly
for debugging purposes and performance judgment.
0*
Normal mode
1
ADC Test mode
0
DAC_TEST R/W
DAC Test mode; in this test mode an internally generated
sine wave is given out to video and sound DAC. The
amplitude at DAC output is −1.7 dBFS. The frequency can
be set by DTO_PC. Please use the following formula:
f = -^D----^T---_2O---₂-^_-₄--^P----^C--- × 13.5 MHz . Due to the sampling theorem
only frequencies up to 6.75 MHz can be generated. This
feature is intended mainly for debugging purposes and
performance judgment.
0*
Normal mode
1
DAC Test mode
X
don’t care if ADC_TEST = 1
9.3.15 Chip identification and Standby mode
Table 48. IDENTITY register (address 2Fh) bit description
Bit Symbol
Access Value
Description
7 to 0 IDENTITY[7:0] R
1000 1010 chip identification, value corresponds to TDA8295
TDA8295_1
Product data sheet
Rev. 01 — 4 February 2008
© NXP B.V. 2008. All rights reserved.
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