tda9874h NXP Semiconductors, tda9874h Datasheet - Page 22

• Manufacturer Part Number: tda9874h
• Description: Digital Tv Sound Demodulator/decoder
• Manufacturer: NXP Semiconductors

Philips Semiconductors
7.3.6
The default setting at power-up is 0000 0000.
Table 21 Demodulator configuration register (subaddress 9)
Table 22 Description of the demodulation configuration register bits
Table 23 Identification mode
Table 24 Channel 2 receive mode
7.3.6.1
It is recommended to switch the FM sound mode identification off whenever the received program is not a terrestrial
2-carrier sound. Switching the identification off will reset the associated hardware to a defined state.
2000 Jun 26
CH2MOD1
Digital TV sound demodulator/decoder
IDMOD1
IDMOD1
BIT
7
7
6
5
4
3
2
1
0
0
0
1
1
0
0
1
D
EMODULATOR CONFIGURATION REGISTER
Notes
CH1MODE
CH2MOD1
CH2MOD0
CH2MOD0
CH1WIDE
SYMBOL
IDMOD0
IDMOD1
IDMOD0
IDMOD0
IDAREA
6
0
1
0
1
0
1
0
Identification mode for FM sound: these bits define the integrator time of the
FM identification. A valid result may be expected after twice this time has expired, at the
latest. The longer the time, the more reliable the identification (see Table 23).
Application area for FM identification: bit IDAREA = 1 selects FM identification
frequencies in accordance with the specification for Korea. If bit IDAREA = 0 the
frequencies for Europe are selected (B/G and D/K standard).
this bit is not used and should be set to logic 0
Channel 2 receive mode: these bits control the hardware for the second sound carrier in
accordance with Table 24. NICAM mode employs a wider bandwidth of the decimation
filters than FM mode.
Channel 1 bandwidth: bit CH1WIDE = 1 switches the decimation filters for the first
sound carrier to a wide bandwidth, so that the main sound carrier of a satellite channel
with its larger deviation can be handled without additional distortion. If bit CH1WIDE = 0
the bandwidth is narrow to cope with the intermodulation requirements of FM stereo.
Channel 1 receive mode: bit CH1MODE = 1 selects the hardware for the first sound
carrier to operate in AM mode. If bit CH1MODE = 0 the FM mode is selected. This
applies to both terrestrial and satellite FM reception.
IDAREA
5
4
22
CH2MOD1
IDENTIFICATION MODE
3
DESCRIPTION
CHANNEL 2
off/reset
medium
NICAM
slow
fast
FM
AM
CH2MOD0
2
CH1WIDE
1
Product specification
TDA9874H
CH1MODE
0