cx25840 Conexant Systems, Inc., cx25840 Datasheet - Page 248

• Manufacturer Part Number: cx25840
• Description: Video Decoder And Broadcast Audio
• Manufacturer: Conexant Systems, Inc.

Register Map
5-106
Analog AGC Hysteresis1
[7:6]
[5:0]
Analog AGC Hysteresis2
[7:6]
[5:0]
Analog AGC Control
[7]
[6]
[5:0]
AFE 12DB ENABLE
[7]
[6]
[5:0]
Bits
Bits
Bits
Bits
RO
RW
RO
RW
RO
RW
RW
RW
RW
RW
Type
Type
Type
Type
0
0
0x20
00
0x05
00
0x09
0
0
0x0E
Default
Default
Default
Default
RESERVED
AAGC_HYST1
RESERVED
AAGC_HYST2
AFE_12DB_EN
AAGC_DEFAULT_EN
AAGC_DEFAULT
RESERVED
AAGC_GAIN_EN
AAGC_TH
Name
Name
Name
Name
Conexant
Controls the hysteresis of the AGC so that the value to the VGA
is not continually changing, which could cause an undesirable
modulation.
Controls the gain of the AGC feedback.
0 = Disable
1 = Enable
Bypass value for the AGC when AAGC_DEFAULT_EN is
asserted. Controls the AGC error threshold.
Enables a +12 dB gain in the analog front end (AFE). When
using a filtered sound-IF output from a tuner, the signals level is
typically about 100 mVrms. In this case the gain should be
enabled. When the sound IF is not filtered, the output will be
closer to 1 Vrms, so this gain should not be used.
0 = Disable
1 = Enable
Enables bypass of the AGC.
0 = Disable
1 = Enable
Bypass value for the AGC when AAGC_DEFAULT_EN is
asserted.
Controls the hysteresis of the AGC so that the value to the VGA
is not continually changing, which could cause an undesirable
modulation.
Description
Description
Description
Description
CX25840/1/2/3 Data Sheet
Address 0x816
Address 0x817
Address 0x814
Address 0x815
102284B
8/3/05