HD49335F Renesas Electronics Corporation., HD49335F Datasheet - Page 13

• Manufacturer Part Number: HD49335F
• Description: Cds/pga And 10-bit A/d Tg Converter
• Manufacturer: Renesas Electronics Corporation.

HD49335F/HF
Dummy Clamp
It adjusts the mis-clamp which occurs when taking the photo under the highlight conditions. (Like a sun) Normally it
woks with the OB clamp, however when black level is out of the range caused by hightlight enter to OB part, it changes
to clamp processing by dummy bit level. Resister settings are follows.
Rev.1.0, Feb.25.2004, page 13 of 29
CDS_in
Note: OB/Dummy switching part has 1/8 hysteresis of threshold value.
D12, D11, D10 of address H'F7 (Dummy CP)
The amount of offset are changes automatically
depends on PGA gain in the LSI.
0, 0, 0 ; OFF
0, 0, 1 ; +32
0, 1, 0 ; +64
0, 1, 1 ; +96
1, 1, 1 ; +224
SP1
VRT
:
:
BLKFB
SP2
SP1
SH
AMP
Figure 7 Internal Bias Circuitry
D8 to D9 of address H'F7
CDS
AGC
BLKSH
Current
cell
D8, D8 of address H'F7 (DMCG)
The amount of feed back current can be
reduced with only dummy clamp.
Data = 0:1/4
ADC
Clamp level
+
1:1/8
2:1/16
3:1/32
)
)
( +
on/off
(
Detect 8clk
from OBP edge
D10 to D12 of address H'F7
+
DET
OB
+
Dummy
DET
Digital output
Detect 4clk
from OPDM edge