WM8143-12
12-bit/4MSPS CCD Signal Processor
Production Data Nov. 1999 Rev 4
Description
The WM8143-12 integrates the analogue signal
conditioning required by CCD sensors with a 12-bit ADC.
The WM8143-12 requires minimal external circuitry and
provides a cost-effective sensor to digital domain system
solution.
Each of the three analogue conditioning channels
includes reset level clamp, CDS, fine offset level shifting
and programmable gain amplification. The three channels
are multiplexed into the ADC. The output from the ADC is
fed to the output bus pins OP[11:0] via a 12/8 bit
multiplexer, enabled by the OEB signal.
The flexible output architecture allows twelve-bit data to
be accessed either on a twelve-bit bus or via a time-
multiplexed eight-bit bus. The WM8143-12 can be
configured for pixel-by-pixel or line-by-line multiplexing
operation. Reset level clamp and/or CDS features can be
optionally bypassed. The device configuration is
programmed either via a simple serial interface or via an
eight-bit parallel interface.
The serial/parallel interfaces of the WM8143-12 are
control compatible with those of the WM8144-10 and
WM8144-12.
Features
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Reset level clamp
Correlated double sampling (CDS)
Fine offset level shifting
Programmable gain amplification
12-bit ADC with maximum 4 MSPS
Simple clocking scheme
Control by serial or parallel interface
Time multiplexed eight-bit data output mode
32 pin TQFP package
Interface compatible with WM8144-10 and
WM8144-12
Applications
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Flatbed scanners
Sheet feed scanners
Film scanners
CCD sensor interfaces
Contact image sensor (CIS) interfaces
Block Diagram
VRLC
VRU
VRT
VRB
VMID
VSMP
MCLK
RLC
AGND
DGND
DVDD
AVDD
MUX
TIMING CONTROL
CL
VMID
RS
VS
OFFSET
RINP
S/H
CDS
5-BIT REG
8-BIT +
SIGN DAC
S/H
PGA
+
+
WM8143-12
VMID
OFFSET
GINP
S/H
CDS
S/H
PGA
+
+
M
U
X
OEB
12-bit
ADC
12/8
MUX
OP[11:0]
5-BIT REG
8-BIT +
SIGN DAC
VMID
OFFSET
BINP
S/H
CDS
5-BIT REG
8-BIT +
SIGN DAC
CONFIGURABLE
SERIAL/PARALLEL
CONTROL INTERFACE
SDI / DNA
SCK / RNW
SEN / STB
NRESET
S/H
PGA
+
+
VMID
Production Data datasheets contain
final specifications current on
publication date. Supply of products
conforms to Wolfson
Microelectronics' terms and
conditions.
Wolfson Microelectronics
Lutton Court, Bernard Terrace, Edinburgh, EH8 9NX, UK
Tel: +44 (0) 131 667 9386 Fax +44 (0) 131 667 5176
email: sales@wolfson.co.uk
www: http://www.wolfson.co.uk
©
1999 Wolfson Microelectronics Ltd.
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
