HD49335F Datasheet, PDF (9/30 Pages) Renesas Technology Corp – CDS/PGA AND 10-bit A/D TG Converter

HD49335F/HF
7. Adjustment of Black-Level S/H Response Frequency Characteristics
The CR time constant that is used for sampling/hold (S/H) at the black level can be adjusted by changing the
register settings, as shown in table 6.
Table 6 SHSW CR Time Constant Setting
SHSW-fsel (Register setting)
[0] [1] [2] [3] [0] [1] [2] [3] [0] [1] [2] [3] [0] [1] [2] [3] [0] [1] [2] [3] [0] [1] [2] [3] [0] [1] [2] [3] [0] [1] [2] [3]
L L L LHL L L LHL LHHL L L LHLHLHL LHHLHHHL
CR Time Constant (Typ) 2.20 nsec 2.30 nsec 2.51 nsec 2.64 nsec 2.93 nsec 3.11 nsec 3.52 nsec 3.77 nsec
(cutoff frequency conversion) (72 MHz) (69 MHz) (63 MHz) (60 MHz) (54 MHz) (51 MHz) (45 MHz) (42 MHz)
SHSW-fsel (Register setting)
[0] [1] [2] [3] [0] [1] [2] [3] [0] [1] [2] [3] [0] [1] [2] [3] [0] [1] [2] [3] [0] [1] [2] [3] [0] [1] [2] [3] [0] [1] [2] [3]
L L LHHL LHLHLHHHLHL LHHHLHHLHHHHHHH
CR Time Constant (Typ) 4.40 nsec 4.80 nsec 5.87 nsec 6.60 nsec 8.80 nsec 10.6 nsec 17.6 nsec 26.4 nsec
(cutoff frequency conversion) (36 MHz) (33 MHz) (27 MHz) (24 MHz) (18 MHz) (15 MHz) (9 MHz) (6 MHz)
8. The SHAMP frequency characteristics can be adjusted by changing the register settings
and the C4 value of the external pin.
BLKC
31
The settings are shown in table 7.
C
Values other than those shown in the table 7 cannot be used.
Recommendation value of C is 1000 pF
Table 7 SHAMP Frequency Characteristics Setting
SHA-fsel (Register setting)
LoPwr
[0]
[1]
[0]
[1]
[0]
[1]
(Register setting)
L
L
H
L
L
H
"Lo"
230 MHz
116 MHz
75 MHz
6800 pF
10000 pF
13000 pF
(240 pF)
(270 pF)
(300 pF)
"Hi"
100 MHz
49 MHz
32 MHz
10000 pF
15000 pF
22000 pF
(560 pF)
(620 pF)
(750 pF)
Note: Upper line : SHAMP cutoff frequency (Typ)
Middle line : Standard value of C4 (maximum value is not defined)
Lower line : Minimum value of C4 (do not set below this value)
[0]
[1]
H
H
56 MHz
18000 pF
(360 pF)
24 MHz
27000 pF
(820 pF)
Rev.1.0, Feb.25.2004, page 9 of 29