tda8296 NXP Semiconductors, tda8296 Datasheet - Page 25

• Manufacturer Part Number: tda8296
• Description: Tda8296 Digital Global Standard Low If Demodulator For Analog Tv And Fm Radio
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TDA8296
Product data sheet
9.3.2 Diverse functions (includes tuner IF AGC Pin mode)
9.3.3 ADC headroom
Table 14.
Legend: * = default value.
Table 15.
Legend: * = default value.
Bit
7 and 6 T_IF_SEL[1:0] R/W
5 and 4 -
3
2
1
0
Bit
7 to 4 -
3 to 0 ADC_HEADR[3:0] R/W
Symbol
Symbol
-
POL_DET
VID_MOD
IF_SWAP
DIV_FUNC register (address 02h) bit description
ADC_HEADR register (address 03h) bit description
Digital global standard low IF demodulator for analog TV and FM radio
All information provided in this document is subject to legal disclaimers.
Access Value Description
R/W
R/W
R/W
R/W
R/W
Rev. 1 — 3 March 2011
Access Value Description
R/W
00*
01
10
11
00*
0*
0
1*
0*
1
0*
1
0000* not used
0001*
0010
0100
1000
It determines the tuner IF AGC output Pin mode. The
open-drain output can be used in special applications
in need of a higher control voltage.
not used
reserved, must be set to logic 0
The polarity detector ensures the proper polarity of the
video signal. So, the sync impulses of the video output
are near ground level.
Selects video modulation. The only standards with
positive video modulation are L and L-accent.
When HIGH, the demodulator expects a swapped IF
spectrum. This is the case in L-accent standard. This
option is also built in for flexibility reasons.
ADC_HEADR adjusts the needed headroom for the
wanted channel’s own sound carriers and the N − 1
adjacent sound carriers (PC in L-accent standard).
The ADC headroom is related to the sum of all
signals. This function is built in for debugging
purposes.
Normal mode
Open-drain mode
3-state mode
not allowed
polarity detector off
polarity detector on
negative video modulation
positive video modulation
normal IF spectrum expected
swapped IF spectrum expected
ADC headroom 3 dB
ADC headroom 6 dB
ADC headroom 9 dB
ADC headroom 12 dB
TDA8296
© NXP B.V. 2011. All rights reserved.
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