tda8295 NXP Semiconductors, tda8295 Datasheet - Page 33

• Manufacturer Part Number: tda8295
• Description: Tda8295 Digital Global Standard Low If Demodulator For Analog Tv And Fm Radio
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TDA8295_1
Product data sheet
9.3.9 Tuner IF AGC functions
Table 29.
Legend: * = default value.
Table 30.
Legend: * = default value.
Table 31.
Legend: * = default value.
Bit
7
6 to 0 T_IF_AGC_SPEED[6:0] R/W
Bit
7 to 4 UP_LIM[3:0]
3 to 0 LOW_LIM[3:0] R/W
Bit
7
6 to 0 T_FORCE_VAL[6:0]
Symbol
POL_TIF
Symbol
Symbol
T_FORCE
T_IF_AGC_SET register (address 15h) bit description
T_IF_AGC_LIM register (address 16h) bit description
T_IF_AGC_FORCE register (address 17h) bit description
Digital global standard low IF demodulator for analog TV and FM radio
Rev. 01 — 4 February 2008
Access Value
R/W
Access Value
R/W
R/W
Access Value
R/W
1111*
0000*
0*
1
3Fh*
XXh
Description
The tuner IF AGC output voltage can be limited to
interface with concepts having power supply < 3.3 V.
UP_LIM determines the upper limit from
FS (= Fh). The format is straight binary.
LOW_LIM determines the lower tuner IF AGC output
limit from 0 (= 0h) to
binary.
0
1*
000 0001
000 0010
000 0100
000 1000*
001 0000
010 0000
100 0000
set upper limit to maximum
set lower limit to minimum
Description
the tuner IF AGC output voltage can be forced
externally to a fixed voltage, determined by
T_FORCE_VAL
T_FORCE_VAL determines the tuner IF AGC
forced value. So the tuner IF AGC can be fixed to
a certain value for debugging purposes. Format is
straight binary.
tuner IF AGC normal operation
tuner IF AGC output voltage determined by
T_FORCE_VAL
0.5
don’t care if T_FORCE = 0
Description
tuner IF AGC polarity
T_IF_AGC_SPEED determines the tuner
IF AGC loop speed
V
inverted tuner IF AGC polarity
normal tuner IF AGC polarity: the higher
the necessary gain, the higher the IF
AGC voltage
nominal speed (determined by the tuner
IF control slope)
+6 dB nominal
+12 dB nominal
+18 dB nominal
DD(3V3)
18 dB nominal
12 dB nominal
6 dB nominal
1
2
, i.e. 1.65 V nominally
FS (= Fh). The format is straight
TDA8295
© NXP B.V. 2008. All rights reserved.
1
2
FS (= 0h) to
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