WM8146 Datasheet, PDF (1/17 Pages) Wolfson Microelectronics plc – 12-bit(8+4-bit) Linear Sensor Image Processor

WM8146
12-bit (8+4-bit) Linear Sensor Image Processor
Product Preview, January 2000 Rev 1.1
DESCRIPTION
The WM8146 is a 12-bit analogue front end/digitiser IC,
which processes and digitises the analogue output signals
from linear CCD sensors at pixel sample rates of up to
6MSPS.
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. The output from each of these
channels is time multiplexed into a single high-speed 12-bit
Analogue to Digital Converter. The digital output data is
available in 8+4-bit wide multiplexed format, with no missing
codes.
The WM8146 is controlled via a configurable serial
interface, which is compatible with all of Wolfson’s imaging
devices.
Powered from an analogue supply voltage of 5V and a
digital interface supply of either 5V or 3.3V, the WM8146
typically only consumes 175mW when operating from 5V
supplies.
FEATURES
• No missing codes guaranteed
• 6MSPS sample rate
• Colour pixel by pixel or line by line sampling
• Monochrome sampling
• Selectable reset level clamp voltage
• Pixel by pixel or line by line clamping
• Correlated double sampling
• 5-bit programmable gain amplifier
• 8-bit + sign offset adjustment
• 5V or 3.3V digital interface compatibility
• Serial control interface
• 28-pin SOIC package
APPLICATIONS
• Flatbed scanners
• Multi-function peripherals
• Copier scanners
• CCD sensor interfaces
BLOCK DIAGRAM
VRLC
(26)
AVDD VRT
(21) (24)
VRB
(23)
VMID AGND1 AGND2 VSMP MCLK RLC
(25)
(22)
(2)
(5)
(7)
(6)
DGND
(8)
DVDD1
(3)
DVDD2
(10)
VMID
RINP (1)
GINP(28)
BINP(27)
MUX
CL
RS VS
S/H
S/H
CDS
PGA
5-BIT REG
S/H
S/H
CDS
PGA
5-BIT REG
S/H
S/H
CDS
PGA
5-BIT REG
TIMING CONTROL
OFFSET
+
+
8-BIT +
SIGN DAC
VMID
OFFSET
M
+
+
U
X
8-BIT +
SIGN DAC
VMID
OFFSET
+
+
8-BIT +
SIGN DAC
VMID
WM8146
12-bit
ADC
8+4
MUX
CONFIGURABLE
SERIAL CONTROL
INTERFACE
(4) OEB
(13) OP[0]
(14) OP[1]
(15) OP[2]
(16) OP[3]
(17) OP[4]
(18) OP[5]
(19) OP[6]
(20) OP[7]
(11)SDI
(12)SCK
(9) SEN
WOLFSON MICROELECTRONICS LTD
Lutton Court, Bernard Terrace, Edinburgh, EH8 9NX, UK
Tel: [phone]
Fax: [phone]
Email: [e-mail]
http://www.wolfson.co.uk
Product Preview data sheets contain
specifications for products in the formative
phase of development. These products may
be changed or discontinued without notice.
1999 Wolfson Microelectronics Ltd.