LTC1864/LTC1865
µPower, 16-Bit, 250ksps
1- and 2-Channel
ADCs in MSOP
FEATURES
DESCRIPTION
The LTC®1864/LTC1865 are 16-bit A/D converters that
are offered in MSOP and SO-8 packages and operate
on a single 5V supply. At 250ksps, the supply current is
only 850μA. The supply current drops at lower speeds
becausetheLTC1864/LTC1865automaticallypowerdown
between conversions. These 16-bit switched capacitor
successive approximation ADCs include sample-and-
holds. The LTC1864 has a differential analog input with an
adjustable reference pin. The LTC1865 offers a software-
selectable 2-channel MUX and an adjustable reference pin
on the MSOP version.
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16-Bit 250ksps ADCs in MSOP Package
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Single 5V Supply
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Low Supply Current: 850μA (Typ)
Auto Shutdown Reduces Supply Current
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to 2μA at 1ksps
True Differential Inputs
1-Channel (LTC1864) or 2-Channel (LTC1865)
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Versions
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SPI/MICROWIRE™ Compatible Serial I/O
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16-Bit Upgrade to 12-Bit LTC1286/LTC1298
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Pin Compatible with 12-Bit LTC1860/LTC1861
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Guaranteed Operation to +125°C (MSOP Package)
The 3-wire, serial I/O, small MSOP or SO-8 package and
extremely high sample rate-to-power ratio make these
ADCs ideal choices for compact, low power, high speed
systems.
APPLICATIONS
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High Speed Data Acquisition
Portable or Compact Instrumentation
Low Power Battery-Operated Instrumentation
Isolated and/or Remote Data Acquisition
TheseADCscanbeusedinratiometricapplicationsorwith
external references. The high impedance analog inputs
and the ability to operate with reduced spans down to
1V full scale, allow direct connection to signal sources
in many applications, eliminating the need for external
gain stages.
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L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
TYPICAL APPLICATION
Single 5V Supply, 250ksps, 16-Bit Sampling ADC
Supply Current vs Sampling Frequency
1000
1μF
5V
100
10
LTC1864
1
2
3
4
8
7
6
V
V
CC
REF
+
1
IN
IN
SCK
SDO
ANALOG INPUT
0V TO 5V
SERIAL DATA LINK TO
ASIC, PLD, MPU, DSP
OR SHIFT REGISTERS
–
5
0.1
GND
CONV
18645 TA01
0.01
0.01
0.1
1
10
100
1000
SAMPLING FREQUENCY (kHz)
18645 TA02
18645fb
1