SPT7852
DUAL 10-BIT, 20 MSPS, 160 mW A/D CONVERTER
FEATURES
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Dual 10-Bit/20 MSPS Analog-to-Digital Converter
Monolithic CMOS
Internal Track-and-Hold
Low Power Dissipation: 160 mW
4 Vp-p Analog Input Range for Each ADC
Single +5 Volt Power Supply
with Option for 3.3 V Digital Outputs
• Tri-State, TTL-Compatible Outputs
• Overrange Bit
• Selectable Two’s Complement or Straight Binary Output
APPLICATIONS
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Video Set-Top Boxes
Cellular Base Stations
QPSK/QAM RF Demodulation
S-Video Digitizers
Composite Video Digitizers
Portable and Handheld Instrumentation
GENERAL DESCRIPTION
The SPT7852 has two 10-Bit CMOS analog-to-digital con-
verters that can sample data at speeds up to 20 MSPS. It
has excellent low noise performance with a very low typical
power dissipation of only 160 mW—that’s the total power
for
both
converters. The SPT7852 uses a dual configuration
of the proprietary circuit design found in our 10-bit CMOS
single converter family, to achieve its high performance in a
CMOS process.
The SPT7852 is specifically designed for video decoding
applications and is ideal for S-video decoding and decoding
of multiple composite video sources. It also has excellent
application in the area of coherent I/Q demodulation in such
applications as QAM demodulation and TV set-top box con-
verters.
Inputs and outputs are TTL/CMOS-compatible to interface
with TTL/CMOS-logic systems. Output data format is select-
able for either straight binary or two’s complement. The
SPT7852 is available in a 44L TQFP package in commercial
and industrial temperature ranges. It is also available in die
form. For availability of extended temperature ranges,
please contact the factory.
BLOCK DIAGRAM
MSB
Invert
10
VINA
T/H
ADCA
Output
Buffer
Overrange
DA0-9
Reference In
Reference
Ladder
VINB
T/H
ADCB
10
Output
Buffer
Overrange
DB0-9
Clock
Reset
Output
Enable
Timing
Generation
CADEKA [ CADEKA MICROCIRCUITS LLC. ]
