CXD1968AR
AGC_ENH_CTL
Read/Write
RESET: 0x0C
Default R/W
Offset Address: 0x52
Bit
Name
Description
7:6 Reserved
00
R/W
When set the 12-bit AGC and PWM is selected. This
5
AGC_PWM12BITENABLE gives 12-bit resolution on the IFAGC PWM output
instead of 10-bit resolution on the CXD1973Q.
0
R/W
Enhanced AGC update rate. These bits determine the
rate (in ADC samples) at which the AGC target level is
updated when the enhanced AGC is enabled. The
4:1 AGCENHUPDATE
0110
R/W
R/W
update rate in samples is given by;
Samples per update = (AGCENHUPDATE + 1) × 8192
The default is 57,344 samples.
Enhanced AGC enable. When set, the AGC target
level set by the AGC_TARGET register, is
automatically optimized to maximize ADC dynamic
range, once AGC lock has occurred. This improves
performance in channels where the interference
produces non-gaussian distribution in the sampled
input signal, such as channels with large amounts of
PAL ACI. This is not recommended for use with dual
AGC control in ZIF mode.
0
AGC ENHENABLE
0
AGC_MEAN_CX
Read/Write
Description
RESET: 0x04
Default R/W
Offset Address: 0x53
Bit
Name
7:4 Reserved
0000
R/W
Sets the mean value of threshold crossings in enhanced AGC
algorithm. This value determines the number of times a
sample can exceed an internal threshold before the AGC
target value is decreased. The recommended value is “4”.
3:0 AGCMEANCX
0100
R/W
AGC_BWREDOFFSET
Read/Write
RESET: 0x0A
Default R/W
Offset Address: 0x54
Bit
Name
Description
7:4 Reserved
0000
R/W
AGC bandwidth reduction offset. Sets a base level AGC
3:0 AGCBWREDOFFSET gain reduction which is reduced further by AGC_CTL
(AGC BW Reduction) after AGC lock is achieved.
1010
R/W
Note) 1. Higher values result in lower gains, lower bandwidth and longer acquisition times.
2. Lower values result in higher gains, higher bandwidth and shorter acquisition times.
3. To prevent excessive AGC gain fluctuation from too high a bandwidth, it is recommended that
the sum of AGCBWREDOFFSET and AGC_CTL(AGC BW Reduction) should exceed 4.
The default of AGCBWREDOFFSET = 10 maintains compatibility with the CXD1973Q.
- 71 -
SONY [ SONY CORPORATION ]
