TDA8295 Datasheet, PDF (28/77 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
9.3.6 Filter settings
Table 23. FILTERS_1 register (address 0Fh) bit description
Legend: * = default value.
Bit Symbol
Access Value Description
7 to 5 VID_FILT[2:0]
R/W
video low-pass filter to remove all unwanted
frequencies (own sound carriers) above video
content (see Figure 7)
001*
video low-pass filter 4 MHz
010
video low-pass filter 5 MHz
100
video low-pass filter off
4 to 0 NOTCH_FILT[4:0] R/W
The notch filter attenuates the adjacent sound
carrier N − 1, which is located differently
dependent on channel spacing 6 MHz, 7 MHz or
8 MHz (see Figure 8).
0 0001* notch filter for 6 MHz channel spacing
(M/N standard)
0 0010
notch filter for 7 MHz channel spacing
(B standard)
0 0100
notch filter for 8 MHz channel spacing (G/H,
D/K, I, L and L-accent standard)
1 0000 notch/low-pass filter off
10
α_resp(f)
(dB)
−10
−30
001aah358
(1) (2)
−50
−70
0
1
2
3
4
5
6
7
f (MHz)
(1) M/N standard.
(2) All other standards.
Fig 7. Video low-pass filters for sound carrier suppression
TDA8295_1
Product data sheet
Rev. 01 — 4 February 2008
© NXP B.V. 2008. All rights reserved.
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