LTC2356-12/LTC2356-14
Serial 12-Bit/14-Bit, 3.5Msps
Sampling ADCs with Shutdown
FEATURES
DESCRIPTION
TheLTC®2356-12/LTC2356-14are12-bit/14-bit, 3.5Msps
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3.5Msps Conversion Rate
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74.1dB SINAD at 14-Bits, 71.1dB SINAD at 12-Bits
Low Power Dissipation: 18mW
serial ADCs with differential inputs. The devices draw
only 5.5mA from a single 3.3V supply and come in a
tiny 10-lead MSOP package. A Sleep shutdown feature
further reduces power consumption to 13µW. The com-
bination of speed, low power and tiny package makes the
LTC2356-12/LTC2356-14suitableforhighspeed,portable
applications.
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3.3V Single Supply Operation
2.5V Internal Bandgap Reference can be Overdriven
3-Wire SPI-Compatible Serial Interface
Sleep (13µW) Shutdown Mode
Nap (4mW) Shutdown Mode
80dB Common Mode Rejection
The80dBcommonmoderejectionallowsuserstoeliminate
ground loops and common mode noise by measuring
signals differentially from the source.
1.25V Bipolar Input Range
Tiny 10-Lead MSOP Package
The devices convert –1.25V to 1.25V bipolar inputs
APPLICATIONS
+
differentially. The absolute voltage swing for A
and
IN
–
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A
extends from ground to the supply voltage.
Communications
IN
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Data Acquisition Systems
Theserialinterfacesendsouttheconversionresultsduring
the 16 clock cycles following a CONV rising edge for com-
patibility with standard serial interfaces. If two additional
clock cycles for acquisition time are allowed after the data
stream in between conversions, the full sampling rate of
3.5Msps can be achieved with a 63MHz clock.
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Uninterrupted Power Supplies
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Multiphase Motor Control
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Multiplexed Data Acquisition
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RFID
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
SoftSpan is a trademark of Linear Technology Corporation. All other trademarks are the property
of their respective owners.
BLOCK DIAGRAM
10µF 3.3V
THD, 2nd and 3rd vs Input Frequency
for Differential Input Signals
–50
7
V
LTC2356-14
DD
–56
+
–
THREE-
STATE
SERIAL
OUTPUT
PORT
A
A
–62
IN
IN
1
2
+
THD
2nd
3rd
14-BIT ADC
SDO
–68
–74
–80
–86
–92
S & H
8
–
14
V
REF
3
4
10
9
CONV
SCK
2.5V
REFERENCE
TIMING
LOGIC
10µF
GND
5
–98
–104
2356 BD
6
11
0.1
1
10
100
EXPOSED PAD
FREQUENCY (MHz)
2356 G02
2356fb
1