LTC1864/LTC1865
µPower, 16-Bit, 250ksps
1- and 2-Channel
ADCs in MSOP
DESCRIPTION
FEATURES
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16-Bit 250ksps ADCs in MSOP Package
Single 5V Supply
Low Supply Current: 850μA (Typ)
Auto Shutdown Reduces Supply Current
to 2μA at 1ksps
True Differential Inputs
1-Channel (LTC1864) or 2-Channel (LTC1865)
Versions
SPI/MICROWIRE™ Compatible Serial I/O
16-Bit Upgrade to 12-Bit LTC1286/LTC1298
Pin Compatible with 12-Bit LTC1860/LTC1861
Guaranteed Operation to +125°C (MSOP Package)
APPLICATIONS
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High Speed Data Acquisition
Portable or Compact Instrumentation
Low Power Battery-Operated Instrumentation
Isolated and/or Remote Data Acquisition
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
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
because the LTC1864/LTC1865 automatically power down
between conversions. These 16-bit switched capacitor
successive approximation ADCs include sample-andholds. The LTC1864 has a differential analog input with an
adjustable reference pin. The LTC1865 offers a softwareselectable 2-channel MUX and an adjustable reference pin
on the MSOP version.
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.
These ADCs can be used in ratiometric applications or with
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.
TYPICAL APPLICATION
Single 5V Supply, 250ksps, 16-Bit Sampling ADC
Supply Current vs Sampling Frequency
1000
1μF
5V
LTC1864
1
2
ANALOG INPUT
0V TO 5V
3
4
VREF
VCC
IN+
SCK
IN–
SDO
GND
CONV
8
7
6
5
SERIAL DATA LINK TO
ASIC, PLD, MPU, DSP
OR SHIFT REGISTERS
SUPPLY CURRENT (μA)
100
10
1
0.1
18645 TA01
0.01
0.01
0.1
10
100
1
SAMPLING FREQUENCY (kHz)
1000
18645 TA02
18645fb
1