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LTC1279
12-Bit, 600ksps Sampling
A/D Converter with Shutdown
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ESCRIPTIO
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Single Supply 5V or ±5V Operation
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Sample Rate: 600ksps
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70dB S/(N + D) and 74dB THD at Nyquist
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Power Dissipation: 60mW Typ
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Power Shutdown with Instant Wake-Up
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Internal Reference Can Be Overdriven Externally
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Internal Synchronized Clock; No Clock Required
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High Impedance Analog Input
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Input Range: 0V to 5V or ±2.5V
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New Flexible, Friendly Parallel Interface Eases
Connections to DSPs and FIFOs
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24-Pin SO Wide Package
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The LTC
®
1279 is a 1.4µs, 600ksps, sampling 12-bit A/D
converter which draws only 60mW from a single 5V or
±5V supplies. This easy-to-use device comes complete
with a 160ns sample-and-hold, a precision reference and
an internally trimmed clock. Unipolar and bipolar conver-
sion modes add to the flexibility of the ADC. The low
power dissipation is reduced even more, drawing only
8.5mW in power shutdown mode. Instant wake-up from
power shutdown allows the converter to be powered
down even during brief inactive periods.
The LTC1279 converts 0V to 5V unipolar inputs from a
single 5V supply and ±2.5V bipolar inputs from ±5V
supplies. Maximum DC specs include ±1LSB INL and
±1LSB DNL. Outstanding guaranteed AC performance
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ncludes 70dB S/(N + D) and 78dB THD at the input
frequency of 100kHz over temperature.
The internal clock is trimmed for 1.4µs conversion time.
The clock automatically synchronizes to each sample
command, eliminating problems with asynchronous clock
noise found in competitive devices. A separate conversion
start input and a data-ready signal (BUSY) ease connec-
tions to FIFOs, DSPs and microprocessors.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Single 5V Supply, 600kHz, 12-Bit Sampling A/D Converter
Effective Bits and Signal-to-(Noise + Distortion)
vs Input Frequency
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24
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A
IN
V
REF
AGND
D11(MSB)
D10
D9
D8
D7
D6
D5
D4
DGND
AV
DD
V
SS
BUSY
CS
RD
CONVST
SHDN
DV
DD
D0
D1
D2
D3
LTC1279
+
0.1µF
10µF
2.42V
REFERENCE
OUTPUT
ANALOG INPUT
(0V TO 5V)
10µF
0.1µF
5V
12-BIT
PARALLEL
BUS
µP CONTROL
LINES
LTC1279 • TA01
+
CONVERSION-START INPUT
POWER SHUTDOWN INPUT
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High Speed Data Acquisition
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Digital Signal Processing
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Multiplexed Data Acquisition Systems
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Audio and Telecom Processing
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Spectrum Analysis
FREQUENCY (Hz)
10k
EFFECTIVE NUMBER OF BITS
SIGNAL/(NOISE + DISTORTION) (dB)
100k 1M 5M
1279 G03
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9
8
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5
4
3
2
1
0
74
68
62
56
50
f
SAMPLE
= 600kHz
NYQUIST
FREQUENCY
