ADC12762 Datasheet, PDF (1/20 Pages) National Semiconductor (TI) – 12-Bit, 1.4 MHz, 300 mW A/D Converter with Input Multiplexer and Sample/Hold

June 1999
ADC12762
12-Bit, 1.4 MHz, 300 mW A/D Converter
with Input Multiplexer and Sample/Hold
General Description
Using an innovative multistep conversion technique, the
12-bit ADC12762 CMOS analog-to-digital converter digitizes
signals at a 1.4 MHz sampling rate while consuming a maxi-
mum of only 300 mW on a single +5V supply. The
ADC12762 performs a 12-bit conversion in three
lower-resolution “flash” conversions, yielding a fast A/D with-
out the cost and power dissipation associated with true flash
approaches.
The analog input voltage to the ADC12762 is tracked and
held by an internal sampling circuit, allowing high frequency
input signals to be accurately digitized without the need for
an external sample-and-hold circuit. The ADC12762 features
two sample-and-hold/flash comparator sections which allow
the converter to acquire one sample while converting the
previous. This pipelining technique increases conversion
speed without sacrificing performance. The multiplexer out-
put is available to the user in order to perform additional ex-
ternal signal processing before the signal is digitized.
When the converter is not digitizing signals, it can be placed
in the Standby mode; typical power consumption in this
mode is 250 µW.
Features
n Built-in sample-and-hold
n Single +5V supply
n Single channel or 2 channel multiplexer operation
Key Specifications
n Sampling rate
n Conversion time
n SNR, f_IN= 100 kHz
n Power dissipation (f_s= 1.4 MHz)
n No missing codes over temperature
1.4 MHz (min)
593 ns (typ)
67.5 dB (min)
300 mW (max)
Guaranteed
Applications
n CCD image scanners
n Digital signal processor front ends
n Instrumentation
n Disk drives
n Mobile telecommunications
n Waveform digitizers
ADC12762 Block Diagram
Ordering Information
Commercial (0˚C ≤ T_A ≤ +70˚C)
ADC12762CCV
ADC12062EVAL
TRI-STATE^® is a registered trademark of National Semiconductor Corporation.
© 1999 National Semiconductor Corporation DS012811
DS012811-1
Package
V44 Plastic Leaded Chip Carrier
Evaluation Board
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