A/D Conversion Pcb; Overview - Ricoh VT3500 Service Manual

1 December 1993

9.2 A/D CONVERSION PCB

9.2.1 Overview

Original
PKHTM
VPH
Peak
PKHST
Hold
Circuit
The analog signal generated from the CCD is inverted and amplified in the
A/D conversion PCB. Then, the analog signal is converted into an 8-bit digital
signal and is sent to the image processing PCB. The original background and
the distortion of the light path are monitored to obtain the exact image data.
OS
CCD
PCB
Selector
0
50%
0
1.7V
SHMRT
2-94
A/D Conversion PCB
Signal Inversion &
Amplification
Circuit
A/D
8 bit
Converter
+REF _ REF
Shading
Distortion
Memory
D/A
Converter
VR(+) VR( )
Current/
Voltage
Converter
To Image
Processing
PCB
8 bit
8 bit
_