AK8448 Datasheet, PDF (40/53 Pages) Asahi Kasei Microsystems – 6-Channel Linear Sensor compatible 10 Bit 40 MSPS x 3 Analog Pre-Processor

ASAHI KASEI
Operations
[AK8448]
„ Sensor I/F Mode
AK8448 has three sensor interface modes: CDS, Clamp and DC connect. The sensor
interface mode is selected by Sensor Interface Mode register R0, D7~D6.
z CDS mode
A mode to process the difference Vpix as its pixel level which is between the reference
level Vprec of each pixel from the sensor output signal and its data level Vdata.
Reference level of the sensor signal is sampled at SHR and data level of the sensor
signal is sampled at SHD respectively.
Sampling point is at the falling edge of SHR and SHD respectively.
When polarity of SHR and SHD is inverted by register ( R1, D7 = 1 ), the sampling point
becomes at the rising edge.
CCDINn
SHR
SHD
CLPB
Low
V_prec
V_pix
V_data
Figure 4 CDS Mode Timing Outline
z Clamp mode
A mode to process the difference Vpix as its pixel level which is between the internally
generated Clamp level Vclamp and data level Vdata of the sensor output signal.
Data level of the sensor signal is sampled at SHD.
Internal Clamp
Level
CCDINn
V_clamp
V_pix
V_data
SHR
SHD
CLPB
Figure 5 Clamp Mode Timing Outline
MS1513-E-00
40
2013/02