FEATURES
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LTC1406
Low Power, 8-Bit, 20Msps,
Sampling A/D Converter
DESCRIPTION
The LTC
廬
1406 is a 20Msps, 8-bit, sampling A/D converter
which draws only 150mW from a single 5V supply. This
easy-to-use device includes a high dynamic range sample-
and-hold with a 250MHz bandwidth.
The LTC1406鈥檚 full-scale input range is
鹵1V.
The inputs
can be driven differentially or one input can be tied to a
fixed voltage and the other input driven with a
鹵1V
bipolar
input. Maximum DC specifications include
鹵1LSB
DNL
and INL over temperature. Outstanding AC performance
includes 48.5dB S/(N + D) and 62dB THD with a 1MHz
input; 47.5dB S/(N + D) and 59dB THD at the Nyquist input
frequency of 10MHz.
The unique differential input sample-and-hold can acquire
single-ended or differential input signals up to its 250MHz
bandwidth. The 60dB common mode rejection allows
users to eliminate ground loops and common mode noise
by measuring signals differentially from the source.
The ADC has an 8-bit parallel output port with separate
power supply and ground allowing easy interface to 3V
digital systems. The pipelined architecture has five clock
cycles of data latency.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Low Power, 8-Bit, 20Msps ADC
250MHz Internal Sample-and-Hold
7 Effective Bits at 70MHz Input Frequency
鹵1LSB
DNL and INL Max
Single 5V Supply and 150mW Dissipation
Power Down to 1碌A(chǔ)
True Differential Inputs Reject Common Mode Noise
Accepts Single-Ended or Differential Input Signals
鹵1V
Differential or 2V Single-Ended Input Span
Analog Inputs Common Mode to V
DD
and GND
24-Pin Narrow SSOP Package
APPLICATIONS
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Telecommunications
Wireless Communications
Digital Cellular Telephones
CCDs and Image Scanners
Video Digitizing and Digital Television
Digital Color Copiers
High Speed Undersampling
Personal Computer Video
High Speed Data Acquisition
TYPICAL APPLICATION
Low Power, 20MHz, 8-Bit Sampling ADC
DV
DD
12
CLK
24
CLOCK
CIRCUITRY
23
22
21
A
IN+
A
IN鈥?/div>
7
TRACK-AND-
HOLD AMP
8-BIT
PIPELINE
ADC
DIGITAL
DATA
OUTPUT
DRIVERS
20
19
18
17
2.2V
2.5k
9
AV
DD
4
V
BIAS
1.95k
10
AGND
3
SHDN
5
V
REF
6
AGND
1
OGND
1406 BD
DGND
11
OV
DD
2
Effective Bits and Signal-to-Noise + Distortion
vs Input Frequency
8
7
OF/UF
6
EFFECTIVE BITS
D7
D6
D5
D4
D3
D2
D1
D0
5
4
3
2
1
0
100k
1M
10M
INPUT FREQUENCY (Hz)
8
16
15
U
U
U
50
44
38
S/(N + D) (dB)
32
100M
1406 TA02
1
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