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LTC1608
High Speed, 16-Bit, 500ksps
Sampling A/D Converter
with Shutdown
The LTC
1608 is a 500ksps, 16-bit sampling A/D con-
verter that draws only 270mW from
±5V supplies. This
high performance device includes a high dynamic range
sample-and-hold, a precision reference and a high speed
parallel output. Two digitally selectable power shutdown
modes provide power savings for low power systems.
The LTC1608’s full-scale input range is
±2.5V. Outstand-
ing AC performance includes 90dB S/(N+D) and – 100dB
THD at a sample rate of 500ksps.
The unique differential input sample-and-hold can acquire
single-ended or differential input signals up to its 15MHz
bandwidth. The 68dB common mode rejection allows
users to eliminate ground loops and common mode noise
by measuring signals differentially from the source.
The ADC has
P compatible,16-bit parallel output port.
There is no pipeline delay in conversion results. A separate
convert start input and a data ready signal (BUSY) ease
connections to FlFOs, DSPs and microprocessors.
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A Complete, 500ksps 16-Bit ADC
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90dB S/(N+D) and –100dB THD (Typ)
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Power Dissipation: 270mW (Typ)
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No Pipeline Delay
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No Missing Codes Over Temperature
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Nap (7mW) and Sleep (10
W) Shutdown Modes
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Operates with Internal 15ppm/
°C Reference
or External Reference
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True Differential Inputs Reject Common Mode Noise
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5MHz Full Power Bandwidth
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±2.5V Bipolar Input Range
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36-Pin SSOP Package
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Pin Compatible with the LTC1604
, LTC and LT are registered trademarks of Linear Technology Corporation.
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Telecommunications
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Digital Signal Processing
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Multiplexed Data Acquisition Systems
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High Speed Data Acquisition
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Spectrum Analysis
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Imaging Systems
FREQUENCY (kHz)
0
–40
–20
0
150
200
1608 TA02
–60
–80
50
100
250
–100
–120
–140
AMPLITUDE
(dB)
fSAMPLE = 500kHz
fIN = 98.754kHz
SINAD = 86.7dB
THD = –92.6dB
LTC1608 4096 Point FFT
Circuitry in the LTC1608 is covered under US Patent #5,764,175
FEATURES
DESCRIPTIO
U
APPLICATIO S
U
TYPICAL APPLICATIO
U
2.2
F
10
F
10
F
10
22
F
4
6
DIFFERENTIAL
ANALOG INPUT
±2.5V
REFCOMP
CONTROL
LOGIC
AND
TIMING
B15 TO B0
16-BIT
SAMPLING
ADC
–
+
10
F
5V OR
3V
P
CONTROL
LINES
D15 TO D0
OUTPUT
BUFFERS
16-BIT
PARALLEL
BUS
11 TO 26
1608 TA01
OGND
OVDD
28
29
1
2
AIN
+
AIN
–
SHDN
CS
CONVST
RD
BUSY
33
32
31
30
27
7.5k
LTC1608
3
36
35
10
9
5V
AVDD
DVDD
DGND
VREF
8
AGND
7
AGND
5
AGND
34
–5V
VSS
10
F
2.5V
REF
10
F
1.75X
+