WM8214
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40MSPS 16-bit CCD Digitiser
DESCRIPTION
FEATURES
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16-bit ADC
The WM8214 is a 16-bit analogue front end/digitiser IC
which processes and digitises the analogue output signals
from CCD sensors or Contact Image Sensors (CIS) at pixel
sample rates of up to 40MSPS.
40MSPS conversion rate
Low power – 390mW typical
3.3V single supply operation
Single, 2 or 3 channel operation
Correlated double sampling
The device includes three analogue signal processing
channels each of which contains Reset Level Clamping,
Correlated Double Sampling and Programmable Gain and
Offset adjust functions. Three multiplexers allow single
channel processing. The output from each of these
channels is time multiplexed into a single high-speed 16-bit
Analogue to Digital Converter. The digital output data is
available in 8-bit wide multiplexed format and there is also
an optional single byte output mode, or 4-bit multiplexed
LEGACY mode.
Programmable gain (9-bit resolution)
Programmable offset adjust (8-bit resolution)
Flexible clamp control with programmable clamp voltage
Flexible timing, can be made compatible with WM819X
and WM815X parts.
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8-bit wide multiplexed data output format
8-bit only output mode
An internal 4-bit DAC is supplied for internal reference level
generation. This may be used during CDS to reference CIS
signals or during Reset Level Clamping to clamp CCD
signals. An external reference level may also be supplied.
ADC references are generated internally, ensuring optimum
performance from the device.
4-bit LEGACY multiplexed nibble mode
Internally generated voltage references
28-pin SSOP package, pin compatible with WM8199
Serial control interface
APPLICATIONS
Using an analogue supply voltage of 3.3V and a digital
interface supply of 3.3V, the WM8214 typically only
consumes 390mW.
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High speed USB2.0 compatible scanners
Multi-function peripherals
High-performance CCD sensor interface
Digital Copiers
BLOCK DIAGRAM
VRLC/VBIAS
RSMP VSMP
MCLK
AVDD
DVDD1 DVDD2
VRT VRX VRB
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CLMP RS VS
TIMING CONTROL
WM8214
VREF/BIAS
R
8
M
U
X
OFFSET
DAC
OEB
G
B
RINP
RLC
RLC
CDS
CDS
PGA
9
+
+
+
+
I/P SIGNAL
POLARITY
ADJUST
R
G
B
M
U
X
OP[0]
OP[1]
OP[2]
OP[3]
OP[4]
OP[5]
DATA
O/P
PORT
16-
BIT
ADC
M
U
X
GINP
BINP
PGA
9
8
OFFSET
DAC
I/P SIGNAL
POLARITY
ADJUST
OP[6]
OP[7]/SDO
RLC
CDS
+
PGA
9
+
8
OFFSET
DAC
I/P SIGNAL
POLARITY
ADJUST
CONFIGURABLE
SERIAL
CONTROL
SEN
SCK
SDI
RLC
DAC
4
INTERFACE
DGND
AGND1
AGND2
WOLFSON MICROELECTRONICS plc
Product Preview, March 2004, Rev 1.6
w :: www.wolfsonmicro.com
Copyright 2004 Wolfson Microelectronics plc.